I also fonud this and I send a email to raindrop but no one reply me. Hope it can be fixed soon.

update: raindrop reply me, here is what they say:

Hello!

Firefox team few times in a year complain about something and block extension immediately. This time they don’t like that we use privacy-friendly PlausibleHQ analytics.

I removed it form our build and send new version to review. Hope to get approve soon.

Rustem Mussabekov