With the video editing confusion that is #kdenlive, attempting to delete chunks of a video (i.e. ads) will end in tears. Instead, you make "zones" (which are not "clips") of actual content *around* the ads, then convert the "zones" to "clips", then delete the original video from the "clips" (which are not "zones"), then render (not save, not export) what remains.

I mean, I'm sure there are good reasons for things to be this obtuse, but damn if this is the "easy" video editing app for Linux