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<p>Once request interception is enabled, every request will stall unless it&#x27;s
continued, responded or aborted.</p>
<p>An example of a naïve request interceptor that aborts all image requests:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token keyword" style="color:#00009f">import</span><span class="token plain"> puppeteer </span><span class="token keyword" style="color:#00009f">from</span><span class="token plain"> </span><span class="token string" style="color:#e3116c">&#x27;puppeteer&#x27;</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">(</span><span class="token keyword" style="color:#00009f">async</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">const</span><span class="token plain"> browser </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">await</span><span class="token plain"> puppeteer</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">launch</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">const</span><span class="token plain"> page </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">await</span><span class="token plain"> browser</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">newPage</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">await</span><span class="token plain"> page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">setRequestInterception</span><span class="token punctuation" style="color:#393A34">(</span><span class="token boolean" style="color:#36acaa">true</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> interceptedRequest </span><span class="token operator" style="color:#393A34">=&gt;</span><span
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="multiple-intercept-handlers-and-asynchronous-resolutions">Multiple Intercept Handlers and Asynchronous Resolutions<a href="#multiple-intercept-handlers-and-asynchronous-resolutions" class="hash-link" aria-label="Direct link to Multiple Intercept Handlers and Asynchronous Resolutions" title="Direct link to Multiple Intercept Handlers and Asynchronous Resolutions"></a></h2>
<p>By default Puppeteer will raise a <code>Request is already handled!</code> exception if
<code>request.abort</code>, <code>request.continue</code>, or <code>request.respond</code> are called after any
of them have already been called.</p>
<p>Always assume that an unknown handler may have already called
<code>abort/continue/respond</code>. Even if your handler is the only one you registered,
3rd party packages may register their own handlers. It is therefore important to
always check the resolution status using
<a href="#httprequestisinterceptresolutionhandled">request.isInterceptResolutionHandled</a>
before calling <code>abort/continue/respond</code>.</p>
<p>Importantly, the intercept resolution may get handled by another listener while
your handler is awaiting an asynchronous operation. Therefore, the return value
of <code>request.isInterceptResolutionHandled</code> is only safe in a synchronous code
block. Always execute <code>request.isInterceptResolutionHandled</code> and
<code>abort/continue/respond</code> <strong>synchronously</strong> together.</p>
<p>This example demonstrates two synchronous handlers working together:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">/*</span><br></span><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">This first handler will succeed in calling request.continue because the request interception has never been resolved.</span><br></span><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">*/</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> interceptedRequest </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">isInterceptResolutionHandled</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">continue</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">}</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic">/*</span><br></span><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">This second handler will return before calling request.abort because request.continue was already</span><br></span><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">called by the first handler.</span><br></span><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">*/</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" s
<p>This example demonstrates asynchronous handlers working together:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">/*</span><br></span><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">This first handler will succeed in calling request.continue because the request interception has never been resolved.</span><br></span><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">*/</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> interceptedRequest </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// The interception has not been handled yet. Control will pass through this guard.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">isInterceptResolutionHandled</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// It is not strictly necessary to return a promise, but doing so will allow Puppeteer to await this handler.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">new</span><span class="token plain"> </span><span class="token class-name builtin">Promise</span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">resolve </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// Continue after 500ms</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token function" style="color:#d73a49">setTimeout</span><span cl
<p>For finer-grained introspection (see Cooperative Intercept Mode below), you may
also call
<a href="#httprequestinterceptresolutionstate">request.interceptResolutionState</a>
synchronously before using <code>abort/continue/respond</code>.</p>
<p>Here is the example above rewritten using <code>request.interceptResolutionState</code></p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">/*</span><br></span><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">This first handler will succeed in calling request.continue because the request interception has never been resolved.</span><br></span><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">*/</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> interceptedRequest </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// The interception has not been handled yet. Control will pass through this guard.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">const</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain">action</span><span class="token punctuation" style="color:#393A34">}</span><span class="token plain"> </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">interceptResolutionState</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">action </span><span class="token operator" style="color:#393A34">===</span><span class="token plain"> InterceptResolutionAction</span><span class="token punctuation" style="color:#393A34">.</span><span class="token plain">AlreadyHandled</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// It is not strictly necessary to return a promise, but doing so will allow Puppeteer to await this handler.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token plain"> </span><span class="token keyword" style
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="cooperative-intercept-mode">Cooperative Intercept Mode<a href="#cooperative-intercept-mode" class="hash-link" aria-label="Direct link to Cooperative Intercept Mode" title="Direct link to Cooperative Intercept Mode"></a></h2>
<p><code>request.abort</code>, <code>request.continue</code>, and <code>request.respond</code> can accept an
optional <code>priority</code> to work in Cooperative Intercept Mode. When all handlers are
using Cooperative Intercept Mode, Puppeteer guarantees that all intercept
handlers will run and be awaited in order of registration. The interception is
resolved to the highest-priority resolution. Here are the rules of Cooperative
Intercept Mode:</p>
<ul>
<li>All resolutions must supply a numeric <code>priority</code> argument to
<code>abort/continue/respond</code>.</li>
<li>If any resolution does not supply a numeric <code>priority</code>, Legacy Mode is active
and Cooperative Intercept Mode is inactive.</li>
<li>Async handlers finish before intercept resolution is finalized.</li>
<li>The highest priority interception resolution &quot;wins&quot;, i.e. the interception is
ultimately aborted/responded/continued according to which resolution was given
the highest priority.</li>
<li>In the event of a tie, <code>abort</code> &gt; <code>respond</code> &gt; <code>continue</code>.</li>
</ul>
<p>For standardization, when specifying a Cooperative Intercept Mode priority use
<code>0</code> or <code>DEFAULT_INTERCEPT_RESOLUTION_PRIORITY</code> (exported from <code>HTTPRequest</code>)
unless you have a clear reason to use a higher priority. This gracefully prefers
<code>respond</code> over <code>continue</code> and <code>abort</code> over <code>respond</code> and allows other handlers
to work cooperatively. If you do intentionally want to use a different priority,
higher priorities win over lower priorities. Negative priorities are allowed.
For example, <code>continue({}, 4)</code> would win over <code>continue({}, -2)</code>.</p>
<p>To preserve backward compatibility, any handler resolving the intercept without
specifying <code>priority</code> (Legacy Mode) causes immediate resolution. For Cooperative
Intercept Mode to work, all resolutions must use a <code>priority</code>. In practice, this
means you must still test for <code>request.isInterceptResolutionHandled</code> because a
handler beyond your control may have called <code>abort/continue/respond</code> without a
priority (Legacy Mode).</p>
<p>In this example, Legacy Mode prevails and the request is aborted immediately
because at least one handler omits <code>priority</code> when resolving the intercept:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">// Final outcome: immediate abort()</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">setRequestInterception</span><span class="token punctuation" style="color:#393A34">(</span><span class="token boolean" style="color:#36acaa">true</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> request </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">isInterceptResolutionHandled</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// Legacy Mode: interception is aborted immediately.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">abort</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;failed&#x27;</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">}</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:
<p>In this example, Legacy Mode prevails and the request is continued because at
least one handler does not specify a <code>priority</code>:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">// Final outcome: immediate continue()</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">setRequestInterception</span><span class="token punctuation" style="color:#393A34">(</span><span class="token boolean" style="color:#36acaa">true</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> request </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">isInterceptResolutionHandled</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// Cooperative Intercept Mode: votes to abort at priority 0.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">abort</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;failed&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> </span><span class="token number" style="color:#36acaa">0</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">}</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token
<p>In this example, Cooperative Intercept Mode is active because all handlers
specify a <code>priority</code>. <code>continue()</code> wins because it has a higher priority than
<code>abort()</code>.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">// Final outcome: cooperative continue() @ 5</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">setRequestInterception</span><span class="token punctuation" style="color:#393A34">(</span><span class="token boolean" style="color:#36acaa">true</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> request </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">isInterceptResolutionHandled</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// Cooperative Intercept Mode: votes to abort at priority 10</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">abort</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;failed&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> </span><span class="token number" style="color:#36acaa">0</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">}</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class=
<p>In this example, Cooperative Intercept Mode is active because all handlers
specify <code>priority</code>. <code>respond()</code> wins because its priority ties with
<code>continue()</code>, but <code>respond()</code> beats <code>continue()</code>.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">// Final outcome: cooperative respond() @ 15</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">setRequestInterception</span><span class="token punctuation" style="color:#393A34">(</span><span class="token boolean" style="color:#36acaa">true</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> request </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">isInterceptResolutionHandled</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// Cooperative Intercept Mode: votes to abort at priority 10</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">abort</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;failed&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> </span><span class="token number" style="color:#36acaa">10</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">}</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="cooperative-request-continuation">Cooperative Request Continuation<a href="#cooperative-request-continuation" class="hash-link" aria-label="Direct link to Cooperative Request Continuation" title="Direct link to Cooperative Request Continuation"></a></h2>
<p>Puppeteer requires <code>request.continue()</code> to be called explicitly or the request
will hang. Even if your handler means to take no special action, or &#x27;opt out&#x27;,
<code>request.continue()</code> must still be called.</p>
<p>With the introduction of Cooperative Intercept Mode, two use cases arise for
cooperative request continuations: Unopinionated and Opinionated.</p>
<p>The first case (common) is that your handler means to opt out of doing anything
special the request. It has no opinion on further action and simply intends to
continue by default and/or defer to other handlers that might have an opinion.
But in case there are no other handlers, we must call <code>request.continue()</code> to
ensure that the request doesn&#x27;t hang.</p>
<p>We call this an <strong>Unopinionated continuation</strong> because the intent is to continue
the request if nobody else has a better idea. Use
<code>request.continue({...}, DEFAULT_INTERCEPT_RESOLUTION_PRIORITY)</code> (or <code>0</code>) for
this type of continuation.</p>
<p>The second case (uncommon) is that your handler actually does have an opinion
and means to force continuation by overriding a lower-priority <code>abort()</code> or
<code>respond()</code> issued elsewhere. We call this an <strong>Opinionated continuation</strong>. In
these rare cases where you mean to specify an overriding continuation priority,
use a custom priority.</p>
<p>To summarize, reason through whether your use of <code>request.continue</code> is just
meant to be default/bypass behavior vs falling within the intended use case of
your handler. Consider using a custom priority for in-scope use cases, and a
default priority otherwise. Be aware that your handler may have both Opinionated
and Unopinionated cases.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="upgrading-to-cooperative-intercept-mode-for-package-maintainers">Upgrading to Cooperative Intercept Mode for package maintainers<a href="#upgrading-to-cooperative-intercept-mode-for-package-maintainers" class="hash-link" aria-label="Direct link to Upgrading to Cooperative Intercept Mode for package maintainers" title="Direct link to Upgrading to Cooperative Intercept Mode for package maintainers"></a></h2>
<p>If you are package maintainer and your package uses intercept handlers, you can
update your intercept handlers to use Cooperative Intercept Mode. Suppose you
have the following existing handler:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> interceptedRequest </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">isInterceptResolutionHandled</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">url</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">endsWith</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;.png&#x27;</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token operator" style="color:#393A34">||</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">url</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">endsWith</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;.jpg&#x27;</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">abort</span><span class="token punctuation" style="color:#393A34">(</span><span clas
<p>To use Cooperative Intercept Mode, upgrade <code>continue()</code> and <code>abort()</code>:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;request&#x27;</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> interceptedRequest </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">request</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">isInterceptResolutionHandled</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">return</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token keyword" style="color:#00009f">if</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">url</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">endsWith</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;.png&#x27;</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token operator" style="color:#393A34">||</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">url</span><span class="token punctuation" style="color:#393A34">(</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">endsWith</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style="color:#e3116c">&#x27;.jpg&#x27;</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> interceptedRequest</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">abort</span><span class="token punctuation" style="color:#393A34">(</span><span clas
<p>With those simple upgrades, your handler now uses Cooperative Intercept Mode
instead.</p>
<p>However, we recommend a slightly more robust solution because the above
introduces several subtle issues:</p>
<ol>
<li><strong>Backward compatibility.</strong> If any handler still uses a Legacy Mode
resolution (ie, does not specify a priority), that handler will resolve the
interception immediately even if your handler runs first. This could cause
disconcerting behavior for your users because suddenly your handler is not
resolving the interception and a different handler is taking priority when
all the user did was upgrade your package.</li>
<li><strong>Hard-coded priority.</strong> Your package user has no ability to specify the
default resolution priority for your handlers. This can become important when
the user wishes to manipulate the priorities based on use case. For example,
one user might want your package to take a high priority while another user
might want it to take a low priority.</li>
</ol>
<p>To resolve both of these issues, our recommended approach is to export a
<code>setInterceptResolutionConfig()</code> from your package. The user can then call
<code>setInterceptResolutionConfig()</code> to explicitly activate Cooperative Intercept
Mode in your package so they aren&#x27;t surprised by changes in how the interception
is resolved. They can also optionally specify a custom priority using
<code>setInterceptResolutionConfig(priority)</code> that works for their use case:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token comment" style="color:#999988;font-style:italic">// Defaults to undefined which preserves Legacy Mode behavior</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token keyword" style="color:#00009f">let</span><span class="token plain"> _priority </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">undefined</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic">// Export a module configuration function</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token keyword" style="color:#00009f">export</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">const</span><span class="token plain"> </span><span class="token function-variable function" style="color:#d73a49">setInterceptResolutionConfig</span><span class="token plain"> </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">priority </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> </span><span class="token number" style="color:#36acaa">0</span><span class="token punctuation" style="color:#393A34">)</span><span class="token plain"> </span><span class="token operator" style="color:#393A34">=&gt;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">(</span><span class="token plain">_priority </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> priority</span><span class="token punctuation" style="color:#393A34">)</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token doc-comment comment" style="color:#999988;font-style:italic">/**</span><br></span><span class="token-line" style="color:#393A34"><span class="token doc-comment comment" style="color:#999988;font-style:italic"> * Note that this handler uses `DEFAULT_INTERCEPT_RESOLUTION_PRIORITY` to &quot;pass&quot; on this request. It is important to use</span><br></span><span class="token-line" style="color:#393A34"><span class="token doc-comment comment" style="color:#999988;font-style:italic"> * the default priority when your handler has no opinion on the request and the intent is to continue() by default.</span><br></span><span class="token-line" style="color:#393A34"><span class="token doc-comment comment" style="color:#999988;font-style:italic"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">page</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">on</span><span class="token punctuation" style="color:#393A34">(</span><span class="token string" style=
<p>If your package calls for more fine-grained control over resolution priorities,
use a config pattern like this:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#393A34;--prism-background-color:#f6f8fa"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#393A34;background-color:#f6f8fa"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#393A34"><span class="token keyword" style="color:#00009f">interface</span><span class="token plain"> </span><span class="token class-name">InterceptResolutionConfig</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> abortPriority</span><span class="token operator" style="color:#393A34">?</span><span class="token operator" style="color:#393A34">:</span><span class="token plain"> </span><span class="token builtin">number</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> continuePriority</span><span class="token operator" style="color:#393A34">?</span><span class="token operator" style="color:#393A34">:</span><span class="token plain"> </span><span class="token builtin">number</span><span class="token punctuation" style="color:#393A34">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token punctuation" style="color:#393A34">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic">// This approach supports multiple priorities based on situational</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic">// differences. You could, for example, create a config that</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token comment" style="color:#999988;font-style:italic">// allowed separate priorities for PNG vs JPG.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"></span><span class="token keyword" style="color:#00009f">const</span><span class="token plain"> </span><span class="token constant" style="color:#36acaa">DEFAULT_CONFIG</span><span class="token operator" style="color:#393A34">:</span><span class="token plain"> InterceptResolutionConfig </span><span class="token operator" style="color:#393A34">=</span><span class="token plain"> </span><span class="token punctuation" style="color:#393A34">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> abortPriority</span><span class="token operator" style="color:#393A34">:</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">undefined</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// Default to Legacy Mode</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain"> continuePriority</span><span class="token operator" style="color:#393A34">:</span><span class="token plain"> </span><span class="token keyword" style="color:#00009f">undefined</span><span class="token punctuation" style="color:#393A34">,</span><span class="token plain"> </span><span class="token comment" style="color:#999988;font-style:italic">// Default to Legacy Mode</span><span class="token plain"></span><br></spa
<p>The above solutions ensure backward compatibility while also allowing the user
to adjust the importance of your package in the resolution chain when
Cooperative Intercept Mode is being used. Your package continues to work as
expected until the user has fully upgraded their code and all third party
packages to use Cooperative Intercept Mode. If any handler or package still uses
Legacy Mode, your package can still operate in Legacy Mode too.</p></div></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages"><a class="pagination-nav__link pagination-nav__link--prev" href="/next/guides/docker"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">Docker</div></a><a class="pagination-nav__link pagination-nav__link--next" href="/next/guides/chrome-extensions"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">Chrome Extensions</div></a></nav></div></div><div class="col col--3"><div class="tableOfContents_bqdL thin-scrollbar theme-doc-toc-desktop"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#multiple-intercept-handlers-and-asynchronous-resolutions" class="table-of-contents__link toc-highlight">Multiple Intercept Handlers and Asynchronous Resolutions</a></li><li><a href="#cooperative-intercept-mode" class="table-of-contents__link toc-highlight">Cooperative Intercept Mode</a></li><li><a href="#cooperative-request-continuation" class="table-of-contents__link toc-highlight">Cooperative Request Continuation</a></li><li><a href="#upgrading-to-cooperative-intercept-mode-for-package-maintainers" class="table-of-contents__link toc-highlight">Upgrading to Cooperative Intercept Mode for package maintainers</a></li></ul></div></div></div></div></main></div></div></div><footer class="footer footer--dark"><div class="container container-fluid"><div class="row footer__links"><div class="col footer__col"><div class="footer__title">Community</div><ul class="footer__items clean-list"><li class="footer__item"><a href="https://stackoverflow.com/questions/tagged/puppeteer" target="_blank" rel="noopener noreferrer" class="footer__link-item">Stack Overflow<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://twitter.com/chromedevtools" target="_blank" rel="noopener noreferrer" class="footer__link-item">Twitter<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li><li class="footer__item"><a href="https://goo.gle/devtools-youtube" target="_blank" rel="noopener noreferrer" class="footer__link-item">YouTube<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li></ul></div></div><div class="footer__bottom text--center"><div class="footer__copyright">Copyright © 2023 Google, Inc.</div></div></div></footer></div>
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