Work around intermittent crash when saving snapshot from Data Browser#2710

Merged

aawdls merged 2 commits intoControlSystemStudio:masterfrom DiamondLightSource:ofl568_snapshot_crash

Oct 14, 2021

+8-3

Commits on Oct 13, 2021

Fixing bug causing CSS to occasionally crash when trying to save a snapshot from the databrowser.
rjwills28
committed
Adding comment to why we need to run on the UI thread.
rjwills28
committed