RT 3.5.5 - searching merged tickets issue

If I enter the ticket number of a ticket that’s been merged into another in
the top-right search box, the search produces 0 results. If I enter the
real ID, I can access the ticket fine. Anyone have an idea of what to
fix/where to look before I dive into this? I don’t have much time these
days to open the code anymore :frowning:

-=| Ben