A follow up:
right now are three days I'm running claws-mail-
3.8.0, including some plugins, without any visible issue

Anyone would like to test it ? Should I upload the resulting RPMS and/or SRPMS ?
Note, I started from the available specfiles, that was 3.7.9 and not the current 3.7.10 version, also, for some reason (some dependency ...) I had to remove the geolocation plugin, anyway it wasn't available in previous versions.
AS