Hi, thanks for putting together a great module. I've been testing the 7.x branch.
The one big downside I can see is that when a TINY PNG account hit's it's API limit (if I've understood the code right) the original image toolkit's version of the image will not be overwritten, and there is no easy way to identify that this has happened an to which files.
I think a worthwhile addition would be to save references to the generated image derivative in a table when this happens and provide an interface that allows some or all of those derivatives to be deleted at a time of the site owner's choosing, that way, If my site hit's the APi limit, I can identify it and effectively queue up the images for resending after the limit has been raised / reset.
Closed: won't fix
1.5
Code
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