A weird bug where one selected file looped in the arrange for a few bars is showing 'no clip or multiple clips selected' when it is touching another different clip (referencing a different audio file)
I had A clip warped and looped and selected it from the session view ctrl C to then go to arrange and ctrl V to paste over some audio already on the corresponding track. It was right at the start on the first track.
I then use the ] tool to extend it to the next clip but as soon as it touches the next clip the clip properties disappears and it says 'no clip or multiple clips selected' but all I haven't selected any of the next clip.
Now as I'm still messing with it in the background I just tried dragging the left of what was the second file to go back to the start and cover the first file and the whole clip just vanished completely.