I wanted a text overlay that faded away.
So I created a text clip with the required text and a transparent background in Track 0,
and the main clip in track 1. The text clip ends well before the main clip.
Then I created a PIP transition that varies the transparency from 0 to 100 over
the full length of the text clip.
This works fine except that at the very end of the text clip, the full-opaque text comes
back for one frame.
A similar thing happens if I use a PIP transition with different starting and ending position to cause the
text overlay to drift off the screen. At the very last frame of the text clip, the text comes back to
its original position.
I looked in the .kdenlive project file and removed a line that looked like