So in other words, open it somewhere else then open it in T3 in order to avoid this bug?
I'm having trouble writing exactly what I mean today for some reason, so maybe this will make more sense
Suppose you have a TIFF that you edit in T3, then want to save it as PNG; no can do, at least on my machine with 10.3.3. However, suppose you have an existing
PNG file you want to edit. You can open that PNG with T3, edit it, and save your changes to the existing PNG file. This was useful for me, as I typically use PNG for putting bitmaps into TeX (pdflatex currently supports only PNG or JPEG directly).