1390690 - Splitter for sidebar overlaps with scroll bar

Status: RESOLVED DUPLICATE of bug 1388514

(Firefox :: Theme, defect)

Description

[Tooru Fujisawa [:arai]]

Attachment: screenshot of scrollbar in sidebar, with mouse hovered

Steps to reproduce:
  1. set "Show Scroll bars" to "Always" in macOS System Preference
  2. run Nightly 57.0a1 (2017-08-15) (64-bit)
  3. open bookmark sidebar
  4. open all subtrees and narrow the height of the window so that there's scrollbar in sidebar
  5. hover on the scrollbar
  6. drag scrollbar

actual result:
  more than half of the scrollbar area is actually splitter
  and dragging it resizes the sidebar horizontally, instead of
  scrolling sidebar content vertically

expected result:
  there's no overlap and dragging scrollbar should scroll sidebar vertically

see attached image that shows horizontal resize cursor is displayed on vertical scrollbar