GIMP 2.10 allows multiple page export to .pdf but they have to be on separate layers.
So this plug-in does just that, breaks an active layer into a new image that contains multiple layers (portions of the original layer).
This way we can then export to .pdf while checking "Layers to Pages" option when prompted. Plug-in Menu Location:
Python-Fu/Image into layers...
- Have your large layer selected that you'd like to break into multiple pages.
- Run plug-in, choose width and height (dimesion) of the portions that you'd like to break the layer in step 1 into.
- OK to run
- That's it, it'll create a new image with these layers then you can export to .pdf (as multipage document).