1642931 - Upgrading to Firefox 77 with "network.file.disable_unc_paths" set to true completely breaks extension storage until the prefernce is manually deleted

Status: RESOLVED DUPLICATE of bug 1634267

(WebExtensions :: Untriaged, defect)

Description

[Luke]

Attachment: Console with the pref enabled on FF77

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Firefox/68.0

Steps to reproduce:

1. Set "network.file.disable_unc_paths" to true in Firefox 76, everything works fine for now.

2. Upgrade to Firefox 77.

Actual results:

Now most extensions simply cease to work, for example uBlock Origin won't block anything and its dashboard page will be empty.

The console will also be spammed with the following errors (see attachment):
"Quota failed to persist storage for principlal: [...]"
"Failed to construct a file for path [...]"

Deleting or disabling the preference returns everything to normal.

This happened to me, only after a lot of troubleshooting did I discover "network.file.disable_unc_paths" was the culript, and deleting the preference fixed everything.

Perhaps consider rolling out a hotfix, since there may be a non-inconsequential share of users like myself who have that preference set and are wondering why their extensions are suddenly broken.

Comment 1

[Ben]

Can confirm this also breaks Reddit Enhancement Suite & uBlock Origin completely, setting the following also resolves it alongside the above.

dom.quotaManager.useDOSDevicePathSyntax = false

Comment 2

[Jorge Villalobos [:jorgev] (he/him)]

Maybe dupe of bug 1627692

Comment 4

[Alice0775 White]

Regression window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=26751e4113d8ffe7a6845f9b055a8e40c15ebfce&tochange=1667399cb5c461a3054ed2381806b0c9698fcecf

And this seems to have been fixed in 78.
Fixed Window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=d9a4de01827ad96992c4c5f101b48144c5c93e64&tochange=1422721c3914caba88ad4b8f69b7b0a52a2e0357

Comment 5

[Tom Tung [:tt, :ttung]]

Yeah, it's should be fixed by 78 and it's a dupe of bug 1634267 which unfortunately couldn't catch Firefox 77.

Comment 6

[Rob Wu [:robwu]]

Thanks for the regression range Alice.

I'm glad that it got fixed in 78, it at least means that ESR78 isn't affected.