1151315 - [regression] Scrolling with middle-click on scrollbar no longer works

Status: NEW

(Core :: XUL, defect)

Description

[Ralf Jung]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:37.0) Gecko/20100101 Firefox/37.0 Iceweasel/37.0.1
Build ID: 20150404020439

Steps to reproduce:

Open a website higher than the screen. Middle-click onto the scrollbar.


Actual results:

Nothing.


Expected results:

The scroll position should be set to where I clicked.

This is on Debian testing.

This worked fine with Firefox up to 35. It stopped working in FF 36. It also seems to depend on my GTK theme: With the Adwaita theme, I get the described behavior. With the Oxygen GTK theme, scrolling works.

Also see <https://bugzilla.mozilla.org/show_bug.cgi?id=24117>.

Comment 1

[woprandi]

[bugday-20150406]

Hi, thanks for your report !
I confirm this bug on Linux 64bits with up-to-date Nightly.

I tested on Gnome 3.14 and Plasma 5 without different behavior, middle-click on scrollbar has no effect.

Comment 2

[u554753]

Hi Ralf, Thanks for reporting this issue. I was able to reproduce with the following specs.

Mozilla/5.0 (X11; Linux i686; rv:46.0) Gecko/20100101 Firefox/46.0
Build: 20151222030207

Comment 3

[Wayne Mery (:wsmwk)]

Does this oldie still reproduce?

Comment 4

[Ralf Jung]

Yes. I realized that with the default Gnome theme, left-clicking (instead of middle-clicking) jumps the scroll bar to where I click, so this might be partially just a theme difference, and I have a work-around. Maybe the middle-click is just a KDE thing. Still, using Gnome, Firefox scroll bars behave different than e.g. the scroll bars in the Gnome PDF viewer: in Firefox, middle-click does nothing; in the PDF viewer, middle-click makes the scroll bar move in the direction of where I clicked.