Adventures in editing PDF forms using linux.
So you're editing a multiple page PDF in GIMP you'll find that it imports the pages as layers, which is all very well, but the PDF exporter ignores layers completely, and just exports the visible composite as a single page.
Quite annoying to discover after 35 minutes of painstaking bitmap layered edits.
You could save a page at a time and combine them which is tedious.
But then I discovered this one neat trick ...
You can export them from GIMP as a MNG (which is the animated form of PNG), which exports each layer as a separate animation frame, because of course it does, what a convenient way to animate things.
You can then feed the MNG to ImageMagick convert, targeting PDF which converts every frame back into a PDF page, because of course it does what a convenient way to make a flick book.
This probably would work with GIF animation too.
You're welcome. #2017yearoflinuxonthedesktop
that cms guy