On some pages the “Debugger” pane will not show any files, instead a blank window will be shown:
One example where this happened: https://codepen.io/anon/pen/wZQjQy
I disabled all Add-Ons but the problem remains the same. Private mode also won’t show any files.
Hello,
I’m not able to reproduce your issue.
Could you detail what you are doing exactly to get the blank debugger?
Did you set breakpoints in a source, if so, where?
Could you open the browser console (https://developer.mozilla.org/en-US/docs/Tools/Browser_Console) and copy what’s in there when you have the blank debugger? That would help us know where the issue is.
Thanks!
Not able to reproduce it because this tab is not loading with any webpage right now.
Couldn’t say how or when it happens because I’m not using this tab every day, but it seems not to be linked with the content of the page.
On my computer, both with a small script of an empty HTML5 doc or a Youtube full page, it’s not working.
With the small Javascript, the console is empty, no error, nothing. With Youtube, there is a lot of requests but only CSS errors and 1 cross-origin error, but I think it depends on the content loaded for each user.
I’m using Firefox Developer Edition : 67.0b14 (64 bits) on Windows 10 (x64) 1809 version.
Hope it helps 
@GuillaumeB you say “Not able to reproduce” but later “it’s not working”. So are you experiencing the same problem where the debugger tab remains empty?
@Nicolas_Chevobbe see the screenshot in my first post. On my private computer the debugger tab works as expected but my company’s laptop won’t display it. It might be a problem due to a AD policy that may interfere with Firefox but AFAIK the Developer edition has no AD policies applied.
Exactly, I’ve got the same problem, my debugger tab is always empty.
@GuillaumeB @AlexWayhill by any chance, are you using a Language Pack?
There has been an issue recently with the Debugger on DevEdition: https://bugzilla.mozilla.org/show_bug.cgi?id=1520181
Yes I do ! I’m using the french language pack.
I’ve tried to set the default language pack and the Debugger re-appears just fine.
I hope this bug will be fixed soon.
Thanks for your answer
Same problem here. This had always been working correctly; I made no settings changes to Firefox. Now, my debugger window is completely blank.
I also just had this start suddenly; fiddling with language packs made no difference. The debugger no longer appears with any web page.
I tried renaming my .mozilla folder (on Ubuntu) to reset everything, and the debugger did start working (of course, I lost all of my other settings)
Facing this problem for months now. The issue occurs for private mode only. I am unable to use Firefox for development. Any fix identified? I have the latest version installed.
Hi @Ganesh_Jadhav!
Is the whole DevTools window blank? or only the content of the “Debugger” tab?
If the whole DevTools window is blank (and since you mention private windows), maybe the issue you are facing is Bug 1581093. This regression impacted Firefox 70 and 71, it will be fixed in Firefox 72, which will be released very soon.
Hi,
There appears a full blank rectangle at the bottom of the tab, with adjustable height. The detached devtools window remains the same. Basically, it can’t be attached to the window.
I have switched to firefox developer edition. Which works smooth.
Thanks,
Ganesh
Thanks for checking, the symptoms are really similar to Bug 1581093 so indeed it should be fixed in Firefox 72. And 72 is actually out right now: https://www.mozilla.org/en-US/firefox/72.0/releasenotes/ , so if you want to come back to the regular release channel of Firefox, DevTools should be working once again.
73.0.1 (64 bit) @ Win10, Polish language
Debugger window is always blank (I’ve checked on a few different sites), not able to access or view any code.
Hi,
I got empty debugger tab using Firefox Browser 74.0 (64-bit) @ Windows 10, Japanese language.
firefox -jsconsole
shows a lot of IndexedDB UnknownErr: ActorsParent.cpp:612
Debugger works fine after I deleted AppData\Roaming\Mozilla\Firefox\Profiles\xxx.default\storage\default\