Throw TypeError if computed display dimension is zero

[Djuffin]

Fixes: #926

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💥 Error: 524 💥

PR Preview failed to build. (Last tried on Oct 7, 2026, 5:37 AM UTC).

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<!DOCTYPE html>
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<!--[if gt IE 8]><!--> <html class="no-js" lang="en-US"> <!--<![endif]-->
<head>

<title>w3.org | 524: A timeout occurred</title>
<meta charset="UTF-8" />
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
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<meta name="viewport" content="width=device-width,initial-scale=1" />
<link rel="stylesheet" id="cf_styles-css" href="/cdn-cgi/styles/main.css" />
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<body>
<div id="cf-wrapper">
    <div id="cf-error-details" class="p-0">
        <header class="mx-auto pt-10 lg:pt-6 lg:px-8 w-240 lg:w-full mb-8">
            <h1 class="inline-block sm:block sm:mb-2 font-light text-60 lg:text-4xl text-black-dark leading-tight mr-2">
                <span class="inline-block">A timeout occurred</span>
                <span class="code-label">Error code 524</span>
            </h1>
            <div>
                Visit <a href="https://www.cloudflare.com/5xx-error-landing?utm_source=errorcode_524&utm_campaign=services.w3.org" target="_blank" rel="noopener noreferrer">cloudflare.com</a> for more information.
            </div>
            <div class="mt-3">2026-10-07 05:37:43 UTC</div>
        </header>
        <div class="my-8 bg-gradient-gray">
            <div class="w-240 lg:w-full mx-auto">
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  <div class="relative mb-10 md:m-0">
    
    <span class="cf-icon-browser block md:hidden h-20 bg-center bg-no-repeat"></span>
    <span class="cf-icon-ok w-12 h-12 absolute left-1/2 md:left-auto md:right-0 md:top-0 -ml-6 -bottom-4"></span>
    
  </div>
  <span class="md:block w-full truncate">You</span>
  <h3 class="md:inline-block mt-3 md:mt-0 text-2xl text-gray-600 font-light leading-1.3">
  
    Browser
  
  </h3>
  
  <span class="leading-1.3 text-2xl text-green-success">Working</span>
  
</div>
                    <div id="cf-cloudflare-status" class=" relative w-1/3 md:w-full py-15 md:p-0 md:py-8 md:text-left md:border-solid md:border-0 md:border-b md:border-gray-400 overflow-hidden float-left md:float-none text-center">
  <div class="relative mb-10 md:m-0">
    <a href="https://www.cloudflare.com/5xx-error-landing?utm_source=errorcode_524&#38;utm_campaign=services.w3.org" target="_blank" rel="noopener noreferrer">
    <span class="cf-icon-cloud block md:hidden h-20 bg-center bg-no-repeat"></span>
    <span class="cf-icon-ok w-12 h-12 absolute left-1/2 md:left-auto md:right-0 md:top-0 -ml-6 -bottom-4"></span>
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  <span class="md:block w-full truncate">Paris</span>
  <h3 class="md:inline-block mt-3 md:mt-0 text-2xl text-gray-600 font-light leading-1.3">
  <a href="https://www.cloudflare.com/5xx-error-landing?utm_source=errorcode_524&utm_campaign=services.w3.org" target="_blank" rel="noopener noreferrer">
    Cloudflare
  </a>
  </h3>
  
  <span class="leading-1.3 text-2xl text-green-success">Working</span>
  
</div>
                    <div id="cf-host-status" class="cf-error-source relative w-1/3 md:w-full py-15 md:p-0 md:py-8 md:text-left md:border-solid md:border-0 md:border-b md:border-gray-400 overflow-hidden float-left md:float-none text-center">
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    <span class="cf-icon-server block md:hidden h-20 bg-center bg-no-repeat"></span>
    <span class="cf-icon-error w-12 h-12 absolute left-1/2 md:left-auto md:right-0 md:top-0 -ml-6 -bottom-4"></span>
    
  </div>
  <span class="md:block w-full truncate">services.w3.org</span>
  <h3 class="md:inline-block mt-3 md:mt-0 text-2xl text-gray-600 font-light leading-1.3">
  
    Host
  
  </h3>
  
  <span class="leading-1.3 text-2xl text-red-error">Error</span>
  
</div>
                </div>
            </div>
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        <div class="w-240 lg:w-full mx-auto mb-8 lg:px-8">
            <div class="clearfix">
                <div class="w-1/2 md:w-full float-left pr-6 md:pb-10 md:pr-0 leading-relaxed">
                    <h2 class="text-3xl font-normal leading-1.3 mb-4">What happened?</h2>
                    <p class="mb-2">The origin web server timed out responding to this request.</p><p>The likely cause is an overloaded background task, database or application, stressing the resources on the host web server.</p>
                </div>
                <div class="w-1/2 md:w-full float-left leading-relaxed">
                    <h2 class="text-3xl font-normal leading-1.3 mb-4">What can I do?</h2>
                    
              <h3 class="text-15 font-semibold mb-2">If you're a visitor of this website:</h3>
              <p class="mb-6">Please try again in a few minutes.</p>

              <h3 class="text-15 font-semibold mb-2">If you're the owner of this website:</h3>
              <p>Please refer to the <a rel="noopener noreferrer" href="https://developers.cloudflare.com/support/troubleshooting/http-status-codes/cloudflare-5xx-errors/error-524/">Error 524</a> article:</p>
              <ul class="ml-4">
                <li>Contact your hosting provider; check for long-running processes or an overloaded web server.</li>
                <li>Use status polling of large HTTP processes to avoid this error.</li>
                <li>Run the long-running scripts on a <a rel="noopener noreferrer" href="https://developers.cloudflare.com/dns/proxy-status/#dns-only-records">grey-clouded subdomain</a>.</li>
                <li>Enterprise customers can <a rel="noopener noreferrer" href="https://developers.cloudflare.com/support/troubleshooting/http-status-codes/cloudflare-5xx-errors/error-524/#resolution-on-cloudflare">increase the timeout setting</a> globally or for specific requests using Cache Rules.</li>
              </ul>
                </div>
            </div>
        </div>

        <div class="cf-error-footer cf-wrapper w-240 lg:w-full py-10 sm:py-4 sm:px-8 mx-auto text-center sm:text-left border-solid border-0 border-t border-gray-300">
    <p class="text-13">
      <span class="cf-footer-item sm:block sm:mb-1">Cloudflare Ray ID: <strong class="font-semibold">a46a8b260a3c9ece</strong></span>
      <span class="cf-footer-separator sm:hidden">&bull;</span>
      <span id="cf-footer-item-ip" class="cf-footer-item hidden sm:block sm:mb-1">
        Your IP:
        <button type="button" id="cf-footer-ip-reveal" class="cf-footer-ip-reveal-btn">Click to reveal</button>
        <span class="hidden" id="cf-footer-ip">91.208.207.239</span>
        <span class="cf-footer-separator sm:hidden">&bull;</span>
      </span>
      <span class="cf-footer-item sm:block sm:mb-1"><span>Performance &amp; security by</span> <a rel="noopener noreferrer" href="https://www.cloudflare.com/5xx-error-landing?utm_source=errorcode_524&#38;utm_campaign=services.w3.org" id="brand_link" target="_blank">Cloudflare</a></span>
      
    </p>
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