Remembering this and especially seeing the release of 1.3.0 with the beta label (I hadn't heard of this), I have encouraged me to update a site in production to 1.3.0, all pretty well, all images were hosted on R2 ie S3 compatible (so all good on that), the only thing is that I had to do this we talked about (luceos) as it gave the same error so I guess it will be important for the final release post.
I'm glad it allows you to go saying yes or no with each image, because thanks to that I have been able to notice that it turns out that the thumbnails of the Blog articles (v17development/flarum-blog), detects them as 'deleted' images and that they are nowhere, because as the URL of these images are only in that specific field and normally not added back to the body of the article (where it detects them), it asks if you want to delete them, thanks to that I have been able to go 1 by 1 saying no.
As the number of Blog articles grows I feel it will be a problem/annoyance, would it be possible to take into account that field for cleanups?
Quite surprised at the amount of images people upload and don't end up posting in the final post π
