1350902 - A black horizontal line appears on the scrollbar when the slider is dragged

Status: RESOLVED WORKSFORME

(Core :: Panning and Zooming, defect, P3)

Description

[roxleitan]

Attachment: 2017-03-24_16h14_27.mp4

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:55.0) Gecko/20100101 Firefox/55.0
Build ID: 20170327030203

[Affected versions]:
Nightly 55.0a1

[Affected platforms]:
All platforms: Windows 10 x 64, Mac OS X 10.10

[Steps to reproduce]:
1.Launch Nightly 55.0a1 with a new profile
2.Go to http://www.zapdramatic.com/
3.Drag the slider from the top of the scrollbar and move it down

[Expected result]:
The scrollbar should be moved down without any issues.

[Actual result]: 
The slider is moved down but a black horizontal line appears on the scrollbar (see attached screencast).

Comment 1

[Botond Ballo [:botond] [back on May 21]]

I'm not able to reproduce this. I tested using the latest nightly, on both Windows 10 and Linux (including with scrollbar buttons enabled).

Comment 2

[Kartikaya Gupta (email:[e-mail])]

I was able to repro on Windows 10 when I tried it.

Comment 3

[Timothy Nikkel (:tnikkel)]

I'm guessing invalidation related? So switching tabs and back should fix the problem?

Comment 4

[Kartikaya Gupta (email:[e-mail])]

(In reply to Timothy Nikkel (:tnikkel) from comment #3)
> I'm guessing invalidation related? So switching tabs and back should fix the
> problem?

I think it's invaldation-related, yes. In my case even just letting go of the scrollbar thumb fixes it. I sometimes see multiple lines instead of just one, but they're always pretty close to the "up arrow" button.

Comment 5

[ovidiu boca[:Ovidiu]]

Tested this issue on Mac, Windows, and Ubuntu with FF Nightly 56.0a1(2017-07-12) and FF beta 55.0b8 and I can't reproduce it. I will mark as Resolved WFM. Please reopen it if you are still able to reproduce it.