Chrome devtools erroneously pauses on exception in ignored script

Question

Image speaks for itself; this script is on the debugger's ignore list; yet every time I trigger this exception it is paused upon. I cannot uncheck Pause on caught exceptions because I am trying to pause on a caught exception in another startup script.

Devtools says The debugger will skip stepping through this script, and will not stop on exceptions, but it's doing just that, it is not skipping this script.

I've tried several things, like unignoring/reignoring. Using canary, etc. I have this problem on both my windows and osx machines; so it doesn't seem to be particularly related to my environment.

I am wondering if anyone else has run into this and found a workaround. Thank you.

Answer 1

Problem remains unsolved. Leaving this post here with some unsucessfull tentatives of mine, so someone can build something based on them.

1. Devtools extension API

It is possible to create an add-on that can reach the Developer Tools window and even reach the Sources tab, but once there all I could do was creating new sidepanels or attaching a listener to code text selection changes: chrome.devtools.panels.sources.onSelectionChanged.addListener((x)=>{console.log("onselectionchanged");console.dir(x);});

This API was not enough, could not reach debug status or any interesting sidepanel.

2. Debugging the debugger with a JS debugger

By hitting ctrl-shift-i or ctrl-shift-j over a devtools debug window it is possible to open another devtools debug window, debuging the first one. From there it is possible to write code that detects the banner informing that the file was supposed to be ignored and then click on the continue button:

function breakpointskipper() {
    bnr = document.getElementById("sources-panel-sources-view").querySelector("div.vbox.flex-auto > div > div > div > div.flex-none > div");
    if (!bnr) return;
    bnr = bnr.shadowRoot;
    if (!bnr) return;
    bnr = bnr.querySelector("div");
    if (bnr.ariaLabel != "This script is blackboxed in the debugger") return;
    btn = document.querySelector("div.scripts-debug-toolbar.toolbar");
    if (!btn) return;
    btn = btn.shadowRoot;
    if (!btn) return;
    btn = btn.querySelector("div > button[aria-label=\"Resume script execution\"]");
    if (!btn) return;
    btn.click();
}

It is possible to even attach this breakpontskipper() button presser to an event in the devtools window and automate things, but as soon as you close the debugger being debugged window, it is all over and you have to recreate the code and reattach again. As said before, I wasn't able to make any add-on reach here.

3. Debugging the debugger with a native debugger

One last available option would be using GDB to debug the DevTools and change its behavior, in the chromium documentation it is shown that they have debug symbols available but I didn't try this approach.

Answer 2

Please try the troubleshooting help, and share some feedback. Also it would help greatly if you pasted some script here.

• 1. Please check if your script black boxed like here
• 2. Did you accidentally turn on - break on all exceptions see here
• 3. Force a hard refresh, i.e. clear you cache like here
• 4. Turn off all break points, then do a restore, try again.

More from ref. on chromium bug site

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Update 1: Can you please verify/double check that your file to ignore is actually added to the ignore list.

If you know upfront which files to ignore, head over to Developer Tools > Settings (Cog Icon) > Ignore List. Then add a file name or regex pattern you wish to exclude.

You should see something like