You know that logfile changes as soon as you close the program. It would be too massive to upload if every movie you ever download was kept on file in your log.
I am not talking about the log. I mean a user-specific .txt file that AS puts every link of downloaded videos in. So if I download
https://www.amazon.de/gp/video/detail/xx
, it would save this link in the .txt file. When I visit the site next time, it checks the .txt file for the link, and if it can find it, it will show the indicator icon. Just like adblockers work, they also use lists and if something could be found, it gets removed.
When going with my extensive approach, it would look like this:
Provider videoID Res Lang
Amz xx 1080p, 720p DE, EN, JP
This file could then be saved in the Documents Folder or another user-specified place, so it doesn't get removed when clearing the cache or uninstalling the program.
And sure, you might ask what's about lower-end PCs. Well, Adblock lists have thousands of entries and even on my 10-year old laptop, I can use it just fine. And AS would not remove anything, it would only check for a match. But unlike an adblocker, it would not modify the site. So even if someone already downloaded 1000 movies and 500 seasons, there should be no big issue.
If there is, there can be a checkbox to disable the check if it is going too slow. Or the user can set a timeout, if AS needs more then 10 seconds for example.
Of course this is not high-priority, I just wanted to write it down when I'm at it anyways. But it could help users without a list to avoid double-downloads more easily when they can't remember the name of the show, or if they got it from the Amz P+ channel or P+ itself. (I want to create a list for myself, but it will take quite some time till I even begin).