Know when you can safely ignore console errors caused by Jetpack Boost.
With Jetpack Boost’s “Optimize CSS Loading” feature, we analyze your website and figure out the most important CSS rules to display first (called Critical CSS). Critical CSS helps display your content sooner, so your users don’t have to wait for the entire page to load.
When you enable “Optimize CSS Loading”, the Critical CSS generation process starts, and Jetpack shows green progress bar. If you open your browser’s developer tools, you may notice a few errors depending on the browser you are using.
Behind the scenes, the plugin opens sample pages from your site in a hidden iframe to assist with generating the required Critical CSS. The iframe is configured to use tight security settings, which block any script execution from inside the iframe. As a result, browsers report blocked content in their console.
Since these are safety measures to protect your site, you don’t need to worry about them!
Examples of console errors you might see and can safely ignore:
Blocked script execution in '<URL>' because the document's frame is sandboxed and the 'allowed-scripts' permission is not set.Blocked script execution in 'https://jp.test?jb-generate-critical-css=08174b89cb' because the document's frame is sandboxed and the 'allowed-scripts' permission is not set.
Still need help?
Please contact support. We’re happy to advise.
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