Problem

When concatenating multiple Plots via PdfPages (from backends.backend_pdf) I am interested in having a proper table of contents navigation in the sidebar of my PDF viewer (I first posted this questionhere). As far as I can see from the code this is neither possible out of the box withthe current implementation, nor easy to "hack in" during runtime.

Comparingthe adobe reference (section G.5), one would need to add the outline keyword as well as titles for the respective pages (coming optionally frompdf.savefig in PdfPages or similar).

Unfortunately I'm a bit overwhelmed by the code and not sure if I can contribute this. Please let me know if some extension of the functionality like this is appreciated at all and I'll dig more into this then and see what I'm able to achieve here.