can't deactivate check of read-only/write icals

[Michael Schwarzer]

Hi there,

I've subscribed three Google calendars with my own calendar by adding there ics file adresses. I haven't any rights for them so they're read-only.

Every time starting Thunderbird I'm getting a window asking to convert read-only online ics calendars.

Since I only subscribe to the calendars (like holidays or sports matches), they are as a matter of fact read-only. So every time I uncheck the checkbox below and choose Cancel or uncheck them all and choose convert. However there's no change. I'v ealso tried to unsubscribe an subscribe them again.
One link for example: https://calendar.google.com/calendar/ic ... /basic.ics

How to deactivate this check or accept this as read-only permanently? The query is annoying!

It says:
A check by the provider for Google Calendar has revealed that the calendars listed below
have read-only access to Google Calendar. If you want to provide calendars
with write access as well and therefore want to convert them, please select them below.

[ ] Always check
Convert / Cancel

[Michael Schwarzer]

problem is solved:

I've tried to convert them, though they're read-only and it worked. (Afterwards I've marked these three calendars read-only again.) And this pop-up seems to be gone.