Antialiasing filter having no effect

[Blighty]

(02-12-2019, 03:20 PM)rich2005 Wrote: Your image is an Indexed png and the colormap shows 255 black entries and 1 white entry.

That is strange. When I open that image it is RGB with 2 colours.

(But the last few days I have also been having problems with images where the transparent areas get changed to black - saving to disk first and then opening in Gimp solves this)