Karl Voit writes:
> I guess this relates to ...
>
>   org-babel-exp processing... [25 times]
>
> ... which also pops up some babel result graphics which did not
> happen before.
>
> Was there a change in the default settings or is this a bug?

Yes there was, sorry for that.  I missed something that was going on in
an otherwise inconspicously named function and that unintentionally
changed the conditions for when source blocks are eligible for
evaluation.  Since your setup was affected, may I ask you to apply this
patch after the next update (which should include 302d3780ec) and report
if this fixes the issue you had?