Fix the `treeitem-expanded`/`treeitem-collapsed` images in dark-mode (PR 12666 follow-up)#12679

Merged

timvandermeij merged 1 commit intomozilla:masterfrom Snuffleupagus:pr-12666-followup

Dec 2, 2020

+6-7

Commits on Dec 2, 2020

Fix the treeitem-expanded/treeitem-collapsed images in dark-mode (PR 12666 follow-up)
Snuffleupagus
committed