A user, satonotdead, reports that the text editor and video upload features are broken in Firefox 78.15 ESR, with console errors related to Discourse chat. Others, including sam and Falco, attempt to reproduce the issue but cannot, noting that it works in newer Firefox versions (e.g., 91 ESR) and on different OSes. Falco points out that Firefox 78 ESR is end-of-life and no longer receives security updates, recommending upgrading to Firefox 91 or 102 ESR. david confirms via BrowserStack that Firefox 91 works correctly and links to an MDN note indicating that Firefox < 89 had bugs with execCommand(), which may be causing the issue. sam suggests improving the support page to clarify ESR support status, and david proposes checking the user agent to fall back to HTML view for unsupported versions, as feature-detecting the bug is difficult. The consensus is that the problem stems from using an outdated, unsupported browser version.
Hi there, it seems to be an issue with last update. I tried to upload a video but it seems uploading is broken too.
When I try to use buttons on editor (or upload) in Firefox I see some errors on console regarding to Discourse chat:
Odd, is this still happening now?
Is it only related to videos, can you repro with images?
Here we go: Upload files for free - recording-discourse.mp4 - ufile.io
[MP4 ~5MB file]
Hmmm I am unable to repro with that file? (using Firefox on Linux)
Well, you need to download the MP4, read the first image or reproduce trying to bold your text in Firefox and Discourse.
This is a bold text with keyboard shortcut
This is a bold text with the menu click
Nope, no repro in Firefox for me.
Yeah you need the exact right codecs, removed
That’s a bold tried with buttons.
That’s a bold tried with keyboard.
Sorry but I’m still with the same (without extensions).
Well I recorded with Kazam, but it’s OK:
No luck reproducing here, just tried on firefox on linux. Perhaps try the browser safe mode? Maybe it is browser plugin related.
Regarding that error, it looks somewhat unrelated and I think we fixed it a few days ago.
What version of Firefox are you using? Are you using an ESR release?
78.15 ESR, what’s up with that?
Still not working in safe-mode.
I am not sure if we even had 78.15 in our test matrix.
I think we need to improve our page here to at least call out stuff a bit better:
Depending on one’s interpretation Firefox ESR is either supported or not. We need to make a proper call here. (if unsupported we should display the HTML view)
My guess here @david is that this may be related to the undo support?
Firefox 78 ESR support ended last year from Mozilla. It doesn’t receive security patches anymore. You need to update to the current ESR version (102) or at least the previous one (91) which will be supported for two more months.
I just double checked via BrowserStack, and the toolbar formatting buttons work correctly under Firefox 91 
Yeah, via MDN, Firefox < 89 had bugs with text manipulation:
Before Firefox 89, manipulating the content of
<input>and<textarea>elements usingDocument.execCommand()commands requires workarounds (see bug 1220696).
We run CI on every commit on Firefox ESR. ESR version is the one packaged in the current Debian stable. At the moment it’s ran against 91.11.0.
Can we feature detect 89 and lower so it gets html view without impacting supported browsers?
It’s difficult to feature-detect a bug like this, so I think our only option is to check the user agent:
