Version 5.6-504+ds-1 of ocaml-merlin is marked for autoremoval from testing on Tue 03 Mar 2026. It depends (transitively) on aflplusplus, affected by #1125242. You should try to prevent the removal by fixing these RC bugs.
A new upstream version is available: 5.6.1-504high
A new upstream version 5.6.1-504 is available, you should consider packaging it.