943917 - [Australis] When closing a tab using the close button, the hover state of the closing briefly appears

Status: RESOLVED FIXED

(Firefox :: Tabbed Browser, defect)

Description

[(Currently slow to respond) Philipp Sackl [:phlsa] (Firefox UX) please use needinfo]

Attachment: undesired hover state when closing a tab

This only happens for one animation frame or two. It can be perceived as flickering.

Comment 1

[Mike Conley (:mconley) (:⚙️)]

What's happening is that even though the tabbrowser-tab's visibility is set to hidden when closing the tab[1], the tab-background has its visibility set to visible which makes the tab background stroke appear on hover.

I think the solution here is to make our CSS in browser/themes/shared/tabs.inc.css that draws the background stroke[3] to not do this if the fadein attribute does not exist (which indicates that the tab is closing).

[1]: https://mxr.mozilla.org/mozilla-central/source/browser/base/content/browser.css#114
[2]: https://mxr.mozilla.org/mozilla-central/source/browser/base/content/browser.css#122
[3]: https://mxr.mozilla.org/mozilla-central/source/browser/themes/shared/tabs.inc.css#226

Comment 2

[Dão Gottwald [:dao]]

(In reply to Mike Conley (:mconley) from comment #1)
> What's happening is that even though the tabbrowser-tab's visibility is set
> to hidden when closing the tab[1], the tab-background has its visibility set
> to visible which makes the tab background stroke appear on hover.
> 
> I think the solution here is to make our CSS in
> browser/themes/shared/tabs.inc.css that draws the background stroke[3] to
> not do this if the fadein attribute does not exist (which indicates that the
> tab is closing).

We should fix the code that introduced this bug, in browser/base/content/browser.css.

Comment 3

[Dão Gottwald [:dao]]

This is basically the same as bug 944136.

Comment 4

[(Currently slow to respond) Philipp Sackl [:phlsa] (Firefox UX) please use needinfo]

(In reply to Dão Gottwald [:dao] from comment #3)
> This is basically the same as bug 944136.

Is it? Will fixing the performance regression in bug 944136 automatically also fix the visual issue?

Comment 5

[Dão Gottwald [:dao]]

(In reply to Philipp Sackl [:phlsa] from comment #4)
> (In reply to Dão Gottwald [:dao] from comment #3)
> > This is basically the same as bug 944136.
> 
> Is it? Will fixing the performance regression in bug 944136 automatically
> also fix the visual issue?

Yes, it should.

Comment 6

[Tim Taubert [:ttaubert] (inactive)]

Yes, this will indeed be fixed by bug 944136.

Comment 7

[Tim Taubert [:ttaubert] (inactive)]

Fixed by bug 944136.