Sadly kdenlive is still extremely buggy and slow for me.
Even when using proxy clips which are an absolute necessity to get decent performance I still can’t edit at decent performance. This is on a ryzen 2600 and arc a380 which has no problems with other tools even when editing 4k timelines so long as I use low impact codecs on the timeline.
The insane amount of crashes it has makes it really hard to use, I can get by using autosave but its more tedious then it is worth. I keep coming back and trying kdenlive, but I can just never use it. I hope it does good eventually, but for the forseeable future I dont see that happening.
I have tried both flatpak as well as native and via wine