Ubuntu 20.04.1 LTS What is your Shotcut version (see Help > About Shotcut)? Is it 32-bit?
20.10.31 Can you repeat the problem? If so, what are the steps?
Apply a filter! Delete the clip from the timeline! Undo! Redo multiple times! See that the filter won’t be restored!
To what exactly? Most people most of the time attach filters to clips but they can also be added to the track or Output. I will assume clip for now…
Redo
At this point the clip that you deleted is removed again and so do the filters on it as well too. That is by design. I do not understand what you expect. In case the filter was added to a track or Output, I do not reproduce it.
I can only apply filters to clips in the timeline. I have no idea about having a filter to a track or output. So you assume correctly.
What do I expect after deleting a clip from the timeline that had a filter? I expect to restore the filter if I redo. This is what redoing means - recovering every step. Otherwise, we deal with data loss which is critical.
As I test it now, it works for me, too. Maybe I did describe an unrelated scenario, id est there was another procedure for this anomaly to appear. I think I didn’t click the clip again after the first redoing and so the filter seemed to have disappeared for me. If I meet it again, I let you know. As for now, the alert’s down.
The alert’s up again. It wasn’t removing the clip nor filter. I was hitting ESC while being inside the filter. That just rendered all the changes for this filter obsolete and they aren’t restorable.