SUMMARY

Things seem to get a bit wonky after importing a project from pre-19.04 kdenlive (back when you could have a track with merged video/audio) into post-19.04 kdenlive. The audio/video groupings of the imported older clips feel misaligned/disharmonious with any new AV clips I insert in the newer version of kdenlive. For example, the old clip may occupy tracks V1/A4, but new clip will occupy tracks V1/A1.

STEPS TO REPRODUCE

1. In Kdenlive 18.08.2 (or thereabouts):
1.1. Create a new project.
1.2. Insert a video clip (with audio) into the timeline, into Video 1.
1.3. Insert an audio clip into the timeline, into Audio 1.
1.4. Save the project.

2. In Kdenlive 19.08.0 (or thereabouts):
2.1. Open the saved project.

OBSERVED RESULT

1. There are now 3 video tracks: V3 (Video 3), V2 (Video 2), and V1 (Video 1).
2. There are now 4 audio tracks: A1 (Audio 1), A2 (Audio 2), A3 (Audio 3), A4 (extra audio).
3. The video in V1 is linked with the audio in A4.
4. I cannot drag the video clip in V1 to V2 or V3. Presumably this is because this is trying to move the corresponding audio clip into tracks A5 or A6, which do not exist.
5. Additionally, depending on the length of the clip in A1, I am unable to insert video clips (with audio) into certain segments of V1, even in places that appear empty. Presumably this because this is trying insert the corresponding audio clip for the video clip into A1, which is already occupied by the existing audio clip.

EXPECTED RESULT
1. After importing an old format project, I am able to freely move my video clips between the different existing video tracks.
2. After importing an old format project, I am able to freely insert a video clip into any free space in any video track.

WORKAROUNDS

For this particular simplified case:

1. To be able to move the video clip between the different video tracks, insert two new audio tracks under A4: A5 and A6. This will give the corresponding linked audio tracks room to move.
2. To fix the issue of new video clips being blocked by the existing audio clip: Insert a new audio track A7 under A6, move the old audio clip to A7, and then delete the empty audio tracks A1, A2, and A3. V1 will now be linked to A1, V2 will now be linked to A2, V3 will now be linked to A3, and A4 can be all on its own and avoid hindering the video clips and their linked audio clips.