Adding a second clip to the timeline removes all effects applied to first clip on the timeline
Just built Kdenlive from source (2022-03-17), Running Arch Linux.
Working in 4K on clips that were recorded in Slog-2 picture profile from a Sony A7S II. To re-create the bug:
Select the part of the clip you want to add to the timeline, and drag it in. Add the "Levels" effect, and set the input black and white levels, as well as gamma.
Select the next clip to work on, and select a range from that, and drag it to the timeline.
The effects applied to the first clip on the timeline are now gone.
Adding more clips does not seem to trigger this bug, it's only the second clip added to the timeline, and it only removes the effects from the first clip.