Firefox snap has no access to /tmp profiles path

[benkuly]

When running Firefox as snap, he does't have access to the /tmp directory and therefore firefox cannot load the profile. It was really hard to debug, because FIrefox doesn't fail to start in -headless mode and therefore there is just a karma timeout.

FIrefox solves that by putting tmp files into ~/Downloads/firefox.tmp/.

[jginsburgn]

I did not understand the problem. Can you clarify and provide repro steps?

[benkuly]

Repro: Install Firefox as snap (linux) and remove other installed Firefox.
When running as snap, Firefox has very limited access to the filesystem, as described in the issue description.

[isostatic]

Create a file in /tmp, say using xfce4-screenshooter

$ ls -l /tmp/Screenshot_2022-08-22_11-19-13.jpg 
-rw-rw-r-- 1 me mygroup 87400 Aug 22 11:19 /tmp/Screenshot_2022-08-22_11-19-13.jpg

Try to open the file in Firefox

file:///tmp/Screenshot_2022-08-22_11-19-13.jpg

Reports the following

File not found
Firefox can’t find the file at /tmp/Screenshot_2022-08-22_11-19-13.jpg.
    Check the file name for capitalisation or other typing errors.
    Check to see if the file was moved, renamed or deleted.

Potentially firefox in a snap thinks /tmp is stored in ~/Downloads/firefox.tmp

firefox prevents access to folders like /var, /etc, /opt. but with /tmp it fakes it. Going to "/" does not show all directories either -- creating a root directory "/test", and even chmod/chowning to the user, does not update. This might be because firefox snapshots it on bootup?

Firefox does allow access to /var/tmp, which is updated.

It's inconsistent and not very well explained.

[perry-mitchell]

Any fix for this? Running into it in Karma+Firefox now, Ubuntu 22.04, Firefox 104.0.2:

[oyejorge]

What's your karma config for launching Firefox?

[ipbc-dev]

Hi. So this seems to be the issue I am facing after all.

Unfortunately it seems Firefox from apt is also broken to some extent, just differently so no longer a workaround :(
https://askubuntu.com/questions/1435994/broken-mozilla-firefox-no-text-displays-font-issue

Would be really nice if #47 could be fixed/merged.

Thanks in advance.

[birtles]

Would be really nice if #47 could be fixed/merged.

I went to go and update #47 for merging but I noticed we already have the profile option for specifying the path to an existing profile. Is that enough? Or do we also need a profileName option for loading a profile by name instead?

[ipbc-dev]

Many thanks for your reply. I confirm the profile option works correctly.

        customLaunchers: {
            'FirefoxHeadless': {
                base: 'Firefox',
                flags: [ '-headless' ],
                profile: require('path').join(__dirname, 'tmp'),
            }
        },

I leave this as an exercise to a future reader to define a good, possibly random, location and clean up after test suite completes, if necessary. This should make us able to workaround this annoying bug that Ubuntu snap has.

[wleoncio]

Firefox does allow access to /var/tmp, which is updated.

Cheers for the workaround! I like to have my downloads saved to /tmp, which I've been unable to do on Firefox snap, but /var/tmp is the next best thing. :)