1406333 - The history and bookmarks expand/collapse buttons are heavy responsive

Status: NEW

(Firefox :: Bookmarks & History, defect, P5)

Description

[Iulia Cristescu, QA [:JuliaC] (away, please needinfo? [e-mail])]

[Affected versions]:
- 58.0a1 (2017-10-05)
- 57.0b6 build1 (20171005195903)
- 56.0.1 build2 (20171002220106)

[Affected platforms]:
- Windows 10 x64
- Mac OS X 10.10.5
- Ubuntu 16.04 x86

[Steps to reproduce]:
1. Launch Firefox
2. Open the Bookmarks (or History) sidebar (or the Library) 
3. Choose one entry and click the corresponding expand/collapse button repeatedly

[Expected result]:
- The selected entry is expanded/collapsed every time the expand/collapse button is clicked

[Actual result]:
- The expand/collapse buttons are heavy responsive

[Regression range]:
- This is not a recent regression, as it is reproducible all the way back to Fx 32.0a1