User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:82.0) Gecko/20100101 Firefox/82.0

Steps to reproduce:

• Open browser toolbox e.g. ctrl + alt + shift + i

Actual results:

• Half of the toolbox screen gets taken up by a white container with black text (see attached image)
• Sometimes, this white container never goes away. If I close the dev tools and reopen them, the container comes back during loading and still never goes away. If I delete the chrome_debugger_profile folder, it resets the settings and such but the white container still comes back and still sticks around.
• I haven't noticed anything correlated with the bug where the white container never disappears, just that if it happens, the only way to get it to stop is to restart the entire browser.

Expected results:

• In my opinion there shouldn't be a connection status message at all unless you specifically toggle a setting. It's never been useful to me and has only made it more difficult to start using the toolbox. But regardless it should at least not stick around indefinitely at random times. It gives the dev tools an overall extremely buggy feeling.

There are other bugs too, and I'm not sure if they're connected, but when the white container shows up it almost always coincides with some other bugs:

1. the element picker tool either not working at all, e.g. clicking elements does not actually select them in the DOM tree; or only working if you double-click, e.g. clicking elements once does nothing, clicking elements twice does select them in the DOM tree but also sends an actual click event to the element, making it impossible to select buttons without actually triggering them.

2. the element highlighter and ruler guides (whatever they're called) not showing up at all

3. the element highlighter and ruler guides being drawn BEHIND the elements being highlighted rather than overlayed on top

4. the element highlighter and ruler guides appearing when nothing is selected/hovered in the DOM tree at all and the element picker is not in use, or getting permanently stuck after selecting/hovering something in the DOM tree and staying visible until the browser toolbox is completely closed.

5. ctrl+C and ctrl+V commands not working in the inspector's rule display menu.

6. a weird and hard to describe bug in the style editor where, while typing or editing CSS rules, the style editor randomly "undoes" whatever you typed and scrolls to the top of the stylesheet.

7. the style editor filling up indefinitely with stylesheets until the browser toolbox crashes. This has continuously gotten worse over the last year as the number of sheets shown in the editor keeps growing, particularly the number of inline and duplicate sheets. Idk if it's showing constructable sheets or duplicate shadow DOM sheets, because the style editor doesn't allow you to see the origin of a sheet within its UI. So it's impossible to know whether 2 sheets shown in the style editor have the same source.

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

I've seen this on my machine too.

Honza

This is likely fixed by work done in Bug 1120863 - Browser toolbox starts blank and doesn't function with pending updates
Feel free to reopen if you are still experiencing this issue.

Honza