Henrik Frisk <frisk.h@gmail.com> writes:

> Recently (not sure when) the ics output came out malformed and a newline is
> omitted between the end of one event and the beginning of another:
>
> END:VEVENT
> BEGIN:VEVENT
>
> is now
>
> END:VEVENTBEGIN:VEVENT
>
> I can't figure out wha the pattern is, for some events the output is
> correct.
>
> This is on Org mode version 9.7-pre release_9.6.8-719-gf299fb and emacs 29.1

We recently did some major changes to comply better to the icalendar
specs and introduced new feature. As it usually goes, major changes can
easily introduce new bugs.

Does the attached patch fix the problem for you?