1212409 - [OMTC] Text in location bar causes black square appear in background after resizing the window if lightweight theme (lwtheme) is in use

Status: RESOLVED INCOMPLETE

(Core :: Graphics, defect, P3)

Description

[arni2033]

Attachment: screenshot - [OMTC] Text in location bar causes black square appear in background after resizing the window if lightweight theme (lwtheme) is in use.png

STR:   (Win7_64, Nightly 44, 32bit, ID 20151005030206, new profile, safe mode)
1. Switch window to maximized mode; make sure you have at least 2 buttons on toolbar
2. Select all text on this page (Ctrl+A) and copy it (Ctrl+C)
3. Go to https://addons.mozilla.org/en-US/firefox/addon/carbon-light/ and install that lwtheme
4. Open new tab
5. Paste copied text from Step 1 into urlbar (Ctrl+L, then Ctrl+V),
   go to the start of the text (Home), select all text in urlbar (Ctrl+A)
6. Dock the window to the left side of screen (Win+Left)
7. Wait ~10 seconds, then change window's width a bit by dragging its right border

Result: After Step 6, you see black rectangle in the background. When you wait 10 seconds in Step 7,
        the black rectangle disappears, but when you resize window, it appears again

Expectations: There should be no black rectangles

Note: I see no black rectangles in background if I set layers.offmainthreadcomposition.enabled -> false
      Please don't close this bug if you only tested this on VM on MacOS, because it doesn't use OMTC

Comment 1

[u279076]

Please use mozregression to find the regression window:
http://mozilla.github.io/mozregression/install.html

Comment 2

[arni2033]

Yes, I knew about mozregression, but I'd really love to hear something like «This doesn't happen on my Mac, please test Win» or «I confirm that it happens on Win7, but have no time; If you do have time, please find the regression». That'd add info to the bug. I don't have much time too, actually...

Pushlog
>   https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=63671ebfa2dd4de57a6b652bacfd5d03d7be2655&tochange=3ad4a417e0955bf95fb86e7542e0e77da7d744da

Comment 3

[u279076]

[Tracking Requested - why for this release]:

(In reply to arni2033 from comment #2)
> https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=63671ebfa2dd4de57a6b652bacfd5d03d7be2655&tochange=3ad4a417e0955bf95fb86e7542e0e77da7d744da

Thanks for posting the pushlog. Bas, this implicates your changes in bug 1153609.

Comment 4

[arni2033]

Actually, I found out that to reproduce this I need to open many tabs, so that they took all width of tabs toolbar.
Also, this is very similar to another bug I experienced (wich also involves scrollable items). I believe that they are the same, but that one is a bit tricky to reproduce w/o removable inspector sidebar. I'll do that next week. Tell me if there's an easy way to download exactly those 2 builds.

Comment 5

[Bas Schouten (:bas.schouten)]

Do we have any testcase here that doesn't require the addon? If not it would appear to be that this bug is caused by the addon somehow messing up the layers structure of the browser chrome when using this add-on. Thereby somehow incorrectly suggesting an opaque area where there isn't one. I'm not sure whether this is a bug in the add-on, in layers, or in the code from bug 1153609.

If it were actually a bug in the latter (which I do believe will have triggered the regression), rather than simply a bug exposed in layers or the add-on by that bugfix, I'd expect this to occur in certain in-browser situations as well.

Comment 6

[arni2033]

(In reply to Bas Schouten (:bas.schouten) from comment #5)
> it would appear to be that this bug is caused by the addon somehow messing up the layers structure
You meant, "the addons"? The issue is presented on every lightweight theme I tried on AMO (~5)

Anyway, I figured out that it _always_ happens in browser. It's just not visible because #nav-bar isn't transparent. When I set "#nav-bar { background:transparent!important; }" using Browser Toolbox or userChrome.css - I see the black rectangle described in comment 0.
So the only reason this issue is visible on lwthemes is that they make #nav-bar transparent.

Comment 7

[Ritu Kothari (:ritu) (Inactive, please n-i to RyanVM, jcristau, or pascal)]

Based on the fact that this is not a new regression, this is a wontfix for 47.

Comment 8

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

Set release status flags based on info from the regressing bug 1153609

Comment 9

[Pascal Chevrel:pascalc (PTO until April 26)]

Is that still a valid bug?

Comment 10

[Bob Hood [:bhood]]

Since the regressing bug was fixed, I would guess that it is not. However, since the OP's account is disabled, we can't rely on confirmation from there. Closing as INCOMPLETE.