File > Open and File > Place read BMP files named .dib or .rle (run-length
encoded bitmaps included), Photoshop files named .pdd and PNG files named
.pns, in any letter case. The Open and Place dialogs list them in "All
readable files", "All placeable files" and their format's own filter, and
Glass's Load Texture lists them too. Linked files with these names update
and relink, the Links panel shows their format, and Edit Original opens
them.
The extensions are read-only: exports still write .bmp, .psd and .png, and
an export to a path with one of the new extensions is refused as before.
The desktop packaging does not associate them with the app.