In the given example only one arrow (use instance) is shown (the one with the id 'photoForwardButton', referencing symbol the symbol with the id 'photoForward').
The other use instance with the id 'photoBackButton' does not display. It references the symbol with the id 'photoBack', which again references the symbol 'photoForward' but with a different rotation.
Thank you for having a look at the problem.
Bug confirmed. Thanks for the nice test case - investigating soon.
Created attachment 13422 [details]
test case for use instances in symbol definitions
Bug fixed on my hdd. I just didn't take <symbol> -> <use> -> <symbol> redirections into account. Filing master bug soon to fix this and numerous other use bugs in ToT.
*** This bug has been marked as a duplicate of 12936 ***