Is there a way to run a content script after the page is loaded but before scripts are executed?

Question

I'm writing a browser extension to intercept all the script tags on the page when it's loaded, but before they execute. To be clear, I'm not looking to block the scripts entirely; I just want to intercept and analyze/modify them before they're run.

Is there a way to do this?

I'm aware of onbeforescriptexecute for Firefox and its polyfill for Chrome, but I'm hoping for something more "official" and cross-browser...

[MutationObserver](https://stackoverflow.com/a/59518023), maybe — CertainPerformance, Mar 19 '21 at 01:57
Perhaps a [DOMContentLoaded Event](https://developer.mozilla.org/en-US/docs/Web/API/Window/DOMContentLoaded_event). — StackSlave, Mar 19 '21 at 02:05
@StackSlave I don't think that can be utilized to target specific scripts. — Spectric, Mar 19 '21 at 02:07

score 0 · Accepted Answer · answered Mar 19 '21 at 02:38

0

As answered by CertainPerformance in the comments, you can use a MutationObserver to observe changes to the DOM as shown here: https://stackoverflow.com/a/59518023

answered Mar 19 '21 at 02:38

Is there a way to run a content script after the page is loaded but before scripts are executed?

1 Answers1