My repeat wings are larger on one side than the other! I can’t remember if there’s a place to change this setting. In the meantime I think you’ll agree that they look extremely funny:
Engrave > Music Symbols Editor > Brackets and Braces.
Repeat wings appear to use Bracket bottom, Bracket top, Reversed bracket bottom and Reversed bracket top.
My guess is that you’ve changed the X and Y scales of Reversed bracket bottom to around 110% without scaling the others to match.
That was it!! Many thanks. Must have changed that setting in some sort of fugue state years ago.