Trying to make a one-liner version of 20241008204358 so that I can use it to export all krita files in a directory.

The bash one-liner, along with optipng (something that I almost always want to use when exporting PNGs) looks like this:

for a in *.kra; do file=$(basename $a .kra); unzip -p $file.kra mergedimage.png >$file.png; optipng $file.png; done