DB won't train, 'Unsure' about everything

[Adrian]

I later realised that I'd jumped to a conclusion and got it very wrong.

.ENCODING probably never appeared in a mail.  bogofilter adds it to a
new DB when you create it by training.

I tried this, and it created the line
.ENCODING 2 0 20250218

So I replaced the wrong version ".ENCODING 4 0 20230304" with this new
one.  (Needs to be done in a binary-safe way.)

and it still works.  Maybe bogofilter would have added the missing line
itself, didn't check.

The three 'special' lines mostly look like ordinary tokens, but the
spamcount column is sometimes used for a different purpose.

Matthias, could you explain what the significance of the values is?

Adrian