It had been about 6 months since updating the program so recently I updated Kdenlive to the latest version. Most things where to be as expected but what I did not expect was now every time I select something in the media bin to drop it in to the timeline or drop something in to the media bin, if I have played the timeline since I last interacted with the media bin the program now soft freezes for a consistent 6 or so seconds. This only happens when I play the timeline between interactions and only happens for the media bin not the effects or compositions. If I move multiple items in to the media bin in a row without playing the timeline this freeze does not happen. It only happens when I have played the timeline since I last touched an item in the media bin.
If it was a more infrequently used feature this would be a minor annoyance but as the media bin, I need to be interacting with it multiple times a minute and its getting quite annoying to have to wait an extra 6 seconds nearly every single time. 🫤 that's a 10-15% slowdown on my editing. 

I wish I had better info for you to be able to reproduce this issue but I get the impression this may be one of those cases where it may happen only on my system and not yours so I don't know how much you can do. but at least now we got a reference point for this issue starting. 

Kdenlive: 25.08.1
MLT: 7.33.0
FFmpeg
KDE Frameworks: 6.18.0
Qt: Using 6.9.1 and built against 6.9.1
Windows 11 Version 25H2
Build ABI: x86_64-little_endian-llp64
Kernel: winnt 10.0.26200

I'm using a 1050TI and
AMD Ryson 5 5600X processor