Hello,
When doing the backup, at some point a systray icon is missing, instead the image-missing icon is shown (see picture attached).
The BackInTime default icon (grey background with down arrow) is displayed at the beginning. Then during the backup the icon change to the missing one (not sure if it is related when the files copy begins).
I'am using Elementary OS Loki and BackInTime 1.1.24.
image-missing.pdf