1353769 - [e10s] When dragging tab, vertical line appears at the right side of selected tab

Status: RESOLVED WORKSFORME

(Firefox :: Theme, defect)

Description

[684sigma]

I'm seeing a bug in Firefox Beta 52, Beta 53. It also happens in Nightly 55. Doesn't happen in ESR 45 and with e10s disabled
Sometimes when dragging tab, vertical line appears at the right side of selected tab. Here's how to reproduce it:

1. Open 4 tabs in a new window
2. Drag and drop the third tab to the place of the second tab
3. Start dragging the third tab

Result: vertical line appears in the middle of the curved border of the selected tab
Expected: Normal curve without vertical lines

Comment 1

[Loic]

Could you attach a screenshot of the issue, please.

Comment 3

[684sigma]

So, the screenshot is unnecessary now?

Comment 4

[Loic]

Yes, I saw he issue and it's already reported in the other bug.

Comment 5

[684sigma]

(In reply to Loic from comment #4)
> Yes, I saw he issue and it's already reported in the other bug.

This is not what reported in that other bug. It describes additional border on background tab that is almost unnoticeable, and this bug describes additional border in the selected tab, which is objectively more noticeable (therefore I noticed it).
Are you 100% that it's exactly that bug, or it'll be fixed by that bug? Everybody in bug 1351020 said that it'll be fixed by bug 1346872, but it wasn't. If you're unsure, could you at least set dependency instead of closing?

Comment 6

[Loic]

Next time, when you report a regression, add screenshot and use the tool mozregresion, we will gain some time.
http://mozilla.github.io/mozregression/

Thank you.

Comment 7

[684sigma]

Attachment: vertical line appears at the right side of tab during drag and drop, by reporter.png

Thanks for the tool, I'll try to use it when I can.

In this bug, mozregression-gui generated this regression range:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=7afc8055e8fbd09e5dd86da64e4a06cd98739821&tochange=fa8ec70570e65e1d21c4b301fbfd38ab568230da

So it was regressed by Bug 1157404, just like Bug 1327968, and it'll possibly fix this bug. If you don't mind, I'll add dependency and check this bug once Bug 1327968 is resolved (it's easier to track).

Comment 9

[Jared Wein [:jaws] (please needinfo? me)]

During a triage meeting today with myself and Eric and Amy from UX we were unable to reproduce this bug. It appears to have been "fixed" by switching to square tabs.