I was not able to import a following recurring event via an .ics file:

BEGIN:VEVENT
DTSTART;VALUE=DATE:20250124
DTEND;VALUE=DATE:20250125
RRULE:FREQ=MONTHLY;BYDAY=FR;BYMONTHDAY=23
RRULE:FREQ=MONTHLY;BYDAY=FR;BYMONTHDAY=24
RRULE:FREQ=MONTHLY;BYDAY=MO,TU,WE,TH,FR;BYMONTHDAY=25
SUMMARY:Paycheck
END:VEVENT

I would like to have a possibility to import this. This is supported by e.g. Google Calendar which I have replaced with Proton Calendar.

More broadly this is to have support for importing recurring events with "custom" rules that wouldn't be possible to be created with the Calendar's UI.