1382629 - The scrollbar cannot be moved to the top/bottom

Status: RESOLVED WORKSFORME

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

Description

[roxleitan]

Attachment: 2017-07-20_10h00_07.mp4

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:55.0) Gecko/20100101 Firefox/55.0
Build ID: 20170717063821

[Affected versions]:
Beta 55.0b10

[Affected platforms]:
Windows 10 x 64,  Windows 7, Ubuntu 16.04 x64

[Steps to reproduce]:
1.Launch Beta 55.0b10 with a new profile
2.Go to http://www.playmag.fr/heroesoftomorrow
3.Set the page zoom at 30%
4.Drag the slider from the top of the scrollbar and move it down/up

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

[Actual result]:
The scrollbar cannot be moved to the top/bottom (please see the attached screencast)

Comment 1

[ovidiu boca[:Ovidiu]]

We also used other pages with SVG and we didn't encounter this issue
	
http://museumofwifi.com/              
https://campaigns.f-secure.com/freedome/takecontrol/en_UK/          
https://wetelo.com/

If you turn off the apz.dreg pref this issue is not reproducible. 
We used Chrome and we also saw some issue there, but different.

Comment 2

[ovidiu boca[:Ovidiu]]

I've just tested on Windows 10 x64 with FF beta 55.0b10 x32 build and I can't reproduce the issue.

Comment 3

[ovidiu boca[:Ovidiu]]

I took a closer look and it seems that something is going on, if you drag the scrollbar up and down quickly you will see that it will shrink, you need to pay attention in order to observe this. Only with this web page, we have this issue.

Comment 4

[Milan Sreckovic [:milan] (needinfo for best results)]

Does setting apz.drag.initial.enabled to false help?  How about setting apz.drag.enabled to false?

Comment 5

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

I'm not able to reproduce using the STR in comment 0 on Windows 10 x64. Using FF 55.0b10 (64-bit).

Comment 6

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

From the video and comparing it to my experience the underlying problem might be that the visible portion of the scrollthumb is truncated - i.e. only part of the scrollthumb is being drawn. In the video the size of the scrollthumb is smaller compared to what I see on my machine, even though the page length is about the same (less than ~2 screenfuls).

Comment 7

[roxleitan]

I tested with "apz.drag.initial.enabled" to false and I reproduced the issue.

Also tested on latest Nightly 56.0a1 (Build ID: 20170720030203) and cannot reproduce it following the steps from comment 0.

Comment 8

[Botond Ballo [:botond]]

(In reply to Kartikaya Gupta (email:[e-mail]) from comment #5)
> I'm not able to reproduce using the STR in comment 0 on Windows 10 x64.
> Using FF 55.0b10 (64-bit).

Nor am I. I did notice that the page's height (and therefore the scroll thumb's height) changes as you scroll, which is a bit weird, but it might be intentional.

Comment 9

[Botond Ballo [:botond]]

(In reply to [e-mail] from comment #7)
> Also tested on latest Nightly 56.0a1 (Build ID: 20170720030203) and cannot
> reproduce it following the steps from comment 0.

If you see the issue with Beta, but not with Nightly, it would be interesting to use mozregression to get a "fix window".

Comment 10

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

Are you still able to reproduce this? Based on comment 7 I'm marking this unaffected on 56 and if you can't repro then we should probably just close this.

Comment 11

[roxleitan]

Tested using FF Beta 56.0b11 and latest Nightly 57.0a1 on Windows 10 x64, Windows 7 x64 and Ubuntu 16.04 x64 and couldn't reproduce the issue.

I will mark this as RESOLVED WORKSFORME

Comment 12

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

Thanks!