Amazon has contacted Fire TV app developers to inform them that paid apps and apps with any in-app purchasing options will be temporarily unavailable in the Netherlands, Poland, and Sweden. This means that many apps, including my own Downloader app, will not be installable on Fire TV Sticks in those regions.
Amazon has not given a reason for this temporary change and has not provided a timeframe for when paid apps and apps with in-app purchases will be available again. The Netherlands, Poland, and Sweden are the newest regions to see Fire TV devices added. The Fire TV Stick 4K Max and the 3rd-gen Fire TV Stick were both made available in those regions late last year for the first time. Prior to that, only the Fire TV Stick Basic Edition, which was a stripped-down version of the 2nd-gen Fire TV Stick made for international markets, was available.
Amazon has had issues making paid apps and apps with in-app purchases available in new markets. The Amazon Appstore was made available in Mexico several years ago, however, paid apps and apps with in-app purchases were excluded for most of that time. It wasn’t until this past November that Amazon finally made all apps available in Mexico.
For now, Fire TV users in the Netherlands, Poland, and Sweden will have to make do with only completely free apps. That covers most apps, but many apps that are otherwise free that include optional in-app purchases, such as in-app subscription options or, in the case of my Downloader app, in-app donation buttons, will also be excluded.
As Randy Linden points out in the comments, it appears as though you will still be able to use free apps with in-app purchases during this temporary period. You will just not be able to buy paid
apps or buy the in-app purchases in any apps.
According to the EMail that I received from Amazon Developer support, although paid apps and IAPs are blocked, free apps (even those with IAPs) are still allowed in the restricted regions.
I interpreted that to mean that your apps should still be installable, but donations won’t work.