UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.90 Safari/537.36

Steps to reproduce the problem:
1. Go to a long page
2. Drag scrollbar to the bottom, without releasing the mouse button
3. Move to the left until the scrollbar snaps back to the top

What is the expected behavior?
Since I'm on GTK, the scrollbar should *not* snap back to the top.

What went wrong?
The scrollbar snaps back to the top even though I'm on GTK.

Did this work before? No 

Chrome version: 54.0.2840.90  Channel: stable
OS Version: Arch Linux
Flash Version: 

I'm reopening this bug that was archived for inactivity: https://bugs.chromium.org/p/chromium/issues/detail?id=553072