reSmush.it compatibility

Any chance of adding compatibility with the resmush.it plugin? Image replacement works, but if you use the “Force re-optimize” button from reSmush.it it reverts back to the original image.

Digging into their code, reSmush.it creates a copy of the original image and appends it with “-unsmushed.[ext]”. If your plugin replaced this file (if it exists) with the newly uploaded image (appended with the same modifier), it should fix the reSmush.it re-optimize function.