[Affected versions]: 60.0a1 (BuildId:20180215103933) [Unaffected versions]: 59.0b9 (BuildId:20180209162511) 58.0.2 (BuildId:20180206200532) 52.6.0 esr (BuildId:20180118122319) [Affected platforms]: Windows 10 64bit. macOS 10.13. Ubuntu 16.04 64bit. [Steps to reproduce]: 1. Launch Firefox with a clean profile. 2. Access the about:preferences#privacy page. 3. Click the "Exceptions" button. 4. Add several entries until the scrollbar is displayed. 5. Scroll through the entered entries. [Expected result]: The user can successfully scroll through the entered entries. [Actual result]: The scrolling is performed outside the "Exceptions" window as well. [Regression range]: This is a recent regression: Last good revision: 358ec67834f6960938e60ced3018626f0d0cfd43 First bad revision: 5417b73364be93e83abf43ec1993d4da78396a83 Pushlog: https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=358ec67834f6960938e60ced3018626f0d0cfd43&tochange=5417b73364be93e83abf43ec1993d4da78396a83 [Note] I can see that this issue is reproducible with the "Saved Logins" window as well. For further information regarding this issue please observe the attached screencast.

Hi Miko! It seems that mozregression pointed out Bug 1434243. Can you please have a look into this? Thanks!

Thank you for the report, I will investigate this.

The problem was similar to bug 1118051. Now nsDisplayCompositorHitTestInfo uses roughly the same visible rect logic as nsDisplayLayerEventRegions.

Comment on attachment 8951569 [details] Bug 1438527 - Use non-empty bounds for nsDisplayCompositorHitTestInfo to ensure proper layer assignment https://reviewboard.mozilla.org/r/220886/#review227050

Pushed by mikokm@gmail.com: https://hg.mozilla.org/integration/autoland/rev/34d3b357c867 Use non-empty bounds for nsDisplayCompositorHitTestInfo to ensure proper layer assignment r=mattwoodrow

I managed to reproduce the bug using an older version of Nightly (2018-02-15) on Windows 10 x64. I retested everything on latest Nightly 61.0a1 and beta 60.0b5 using Windows 10 x64, Ubuntu 16.04 x64 and macOS 10.13 and the bug is not reproducing anymore. The user can successfully scroll through the entered entries without scrolling the whole page that is in the background.