new messages not showing

[Mehturt]

Hello list,
I'm using finch 2.10.11 from Debian repository.
I'm a happy user for many years, but recently I noticed one issue.
Sometimes, when I receive a new message, I have notification pop up,
but the actual message is missing.
I'm using a few custom plugins, which were working fine several years,
is it possible that the plugins would cause the message to be missing?
I have searched the support archives of recent months but I don't see
this problem mentioned by anyone.  How can I diagnose this issue?
Thanks.
m.