When I add a new clip to my Project Bin for the first time, it takes some moments to do that, a progress bar appears next to it and begins filling up, taking maybe 20 - 30 sec or so to add a 1.5 hr movie.

Now, if I delete that clip from Project Bin, and go to add it again, it immediately goes back in, no wait time, no progress bar, ready to be used.

I want to erase whatever memory it has and is using to quickly import my clip. I want it to re-build everything and take those several moments as if it's adding the clip for the first time.

I am troubleshooting a complicated problem related to specific clips in my project not working with preview render while others are. I want to be able to delete this pre-existing information that it stored and re-import the clip for the first time. I already deleted everything at AppData\Local\kdenlive\cache (except thumbnail images which seem would be irrelevant to this issue).

I appreciate the assistance, thank you.

This loading time is used by kdenlive to check if the internal content is good (not corrupted) and also to check if the framerate is a variable one (to suggest a conversion) .. these "checks" are stored on RAM... it's not necessary to create caches or something else on the disk.. when a clip is marked "as valid" ... it's not necessary anymore this check, you can't do nothing to erase Kdenlive memory allocated stack using external softwares (or manually BTW)

if you need to reimport the clip checking again it.. just rename the file.