1725772 - browser.tabs.tabMinWidth resets every time browser is closed

Status: UNCONFIRMED

(Core :: Preferences: Backend, defect)

Description

[tia.lahtinen]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0

Steps to reproduce:

I navigated to About:Config and searched for browser.tabs.tabMinWidth
I changed browser.tabs.tabMinWidth to desired number (100) and Saved
Things worked as expected as long as browser was not closed.

I shut my computer down (thus closing browser)
I turned my computer on, and started Firefox. Tabs were back to default length (which is too short for my taste).

Notes: I have one user CSS that affects tab properties among a few other things. I have disabled tab animation, and radded tab separation lines. I have no idea if these would affect the browser.tabs.tabMinWidth setting or not.

I also keep my browser in two windows, of which both have tabs.

Actual results:

browser.tabs.tabMinWidth was reset to default value (0)

Expected results:

browser.tabs.tabMinWidth should have stayed set value (100)

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Firefox::Session Restore' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Comment 2

[u608768]

Session Restore should never change or revert prefs. Is it possible that a different profile was restored? If you created a new profile while browsing in the old one, Firefox will set the new one as default.

Comment 3

[tia.lahtinen]

I'm not sure if that could have happened. Between making this bug report and now I have restarted my computer more than once - and each time the browser.tabs.tabMinWidth has reset to default value/0.

Comment 4

[u608768]

Huh, that's odd. Do other prefs persist across shutdown?

Nothing should be resetting that pref as far as I can tell: https://searchfox.org/mozilla-central/search?q=tabMinWidth&path=&case=false&regexp=false.

(Also, the default for browser.tabs.tabMinWidth is 76, is that what you meant? If it's resetting to 0 then that might be another problem.)

Comment 5

[Andrew McCreight [:mccr8]]

I'll move this to Preferences, as it sounds like the saving and restoring of prefs isn't handled by Session Store.

Comment 6

[Andrew McCreight [:mccr8]]

Or maybe the Core preferences component? I don't know.

Comment 7

[Andrew McCreight [:mccr8]]

If you manually exit the browser and restart the browser, is the preference value restored correctly? How about if you manually exit the browser then turn the computer off and on again?

Comment 8

[tia.lahtinen]

Sorry for the reply delay.
I assumed that "0" just means whatever the default is. Whatever it is, it's far from wide enough for my taste.
I'm unsure what "manually exit" means in this case? I usually don't exit Firefox by clicking the "X" button to close it, because it won't save my preferred way of doing things (it only saves one window's worth of tabs, while crashing it via Task Manager or letting Windows shut it during computer shut off preserves it.

Comment 9

[u608768]

(In reply to tia.lahtinen from comment #8)

I usually don't exit Firefox by clicking the "X" button to close it, because it won't save my preferred way of doing things (it only saves one window's worth of tabs

Checking "Restore previous session" in about:preferences#general, or using Menubar > History > Restore previous session after the browser starts should restore all windows, even if you've closed with the "X" button.

Comment 10

[tia.lahtinen]

The whole thing about closing Firefox with "X" or not is not relevant, I think? Someone mentioned something about checking Firefox is looking up the right profile - how do I do that?

Outside of that, I'm simple resigning to manually setting my preferred tab width in About:config, now.