KMail problem

[Timothy Murphy]

I'm surprised the recent KMail problem has not been solved.
The symptoms in my case, in brief, are

1. I am using KMail on my laptop with dovecot/IMAP
to read mail collected on my desktop;

2. KMail crashes when reading, or even accessing, certain messages.
These are nearly all, if not all, mailing list digests.
I guess the property they have in common might be
that they have a large number of references to other messages or URLs.

I submitted a bugzilla, which bizarrely to me
was declared a duplicate of a bugzilla over a year old
https://bugs.kde.org/show_bug.cgi?id=186502
and which appeared to deal with another symptom,
KMail crashing when it starts.

There are a large number of duplicates listed,
nearly all very recent.

It seems to me fairly obvious that the problem has arisen recently,
and is due to a recent change in KMail (or possibly dovecot).