I did a quick review of our FIXME comments (regex FIXME.*WT-) and found the following list of tickets that are closed but still have an associated FIXME in the codebase:
WT-7470
WT-9860
WT-8747
WT-8947
WT-6180
WT-9048
These comments need to be reviewed and either removed or updated to reflect that work is still required under a new ticket.