Affected versions

• Firefox 89.0
• Firefox 90.0a1

Affected platforms

• macOS 10.15.7
• Ubuntu 20.04
• Windows 10

Steps to reproduce

1. Launch Firefox and access customize mode
2. Drag import bookmarks and then bookmark toolbar items slowly to the toolbar or in the list (the message "For quick access, place your bookmarks here on the bookmarks toolbar" needs to appear in the empty bookmarks toolbar in order to reproduce it)
3. Click on restore defaults
4. Right click on toolbar and select bookmarks toolbar -> always show

Expected result

• The bookmark toolbar items is shown after the quick access message (can see it in the attachment in bug)

Actual result

• Both the bookmark toolbar items and the message are rendered one over another.

Regression range

• Seems to be a regression from 2021-12-03 and onward

• First bad: 2021-12-03
• Last good: 2021-12-02
• Pushlog: https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=ec6a64b639a82e957376c09a71aef7ce62b3a5aa&tochange=f4417c559c57499576484b75a2cc0d2d013cf3fd
• Potential regressor: Bug 1678921 - make empty toolbar disclaimer take up no horizontal space, so the entire toolbar functions as a drag target for bookmarks

Additional notes

• The issue can be seen in the following attachment

After bug 1674091 the message and the bookmarks toolbar item were already both displayed in the toolbar at the same time - that's still a bug, even if they didn't overlap rendering them unreadable. The message should be hidden. So I'm updating the regressor.

The root cause is that we don't update the state of the message in customize mode for reset/undoreset until customization finishes: https://searchfox.org/mozilla-central/rev/bf8d5de8528036c09590009720bc172882845b80/browser/base/content/browser-places.js#1762-1806

Given the niche STR and the fact that this disappears as soon as you leave customize mode, I am inclined to suggest we should wontfix this.

If we did want to fix it, we'd probably need to teach the code to care about reset/undoreset of the toolbar. Jared, WDYT?

(In reply to Catalin Sasca, QA [:csasca] from comment #0)

Expected result

• The bookmark toolbar items is shown after the quick access message (can see it in the attachment in bug)

So to be clear, I dispute that this is expected. ;-)

I think the message should not be visible when there is anything else on the toolbar (in this case, the bookmarks toolbar items).

I'm indifferent to wontfix'ing it. I think you've described the fix well, but I don't think it's worth our time to track this down when we have bugs we could work on that make a bigger difference to our users.