audio clips cannot be pasted to tracks other than "A1"
If you copy and paste an audio clip, it will attempt to paste the clip to track "A1", regardless of the track that was clicked (see attached video). If an audio clip is already present on track A1 at that point, the clip will not be pasted at all.
Tested using Kdenlive 19.04.1-20910f95 x64 AppImage on KDE neon 5.15.