Keep internal links

[faroit]

version 2.6 of the remarkable os supports internal links in PDFs. Without having done deeper analysis, to me it looks like p2r removes hyperlinks in its process. It that' really the case, this would be great to add as a feature.

[GjjvdBurg]

Thanks for reporting this @faroit. Can you provide an example of a file with hyperlinks that works when uploaded directly but not when uploaded with p2r?

[faroit]

Sure: https://arxiv.org/pdf/2103.03206.pdf, for example.

[GjjvdBurg]

Thanks for the link, I can confirm the bug. It seems to happen when cropping, but not when running with the --no-crop flag, which suggests that the problem is in the process_page function. This is strange because the metadata of the pages should be maintained since we switched to pikepdf.

If you'd like to debug this yourself I'd suggest looking there first. Alternatively, finalizing #95 would probably also solve this.

[nzinov]

I suspect that cropping somehow messes with text layer positioning. In addition to links not working I also have weird placement of highlighter when "snap to text" option is enabled. Looks like it snaps to the previous position of text. Then probably hyperlinks are also not gone but just moved to some random place on the page. Hope it makes sense, I don't have good understanding of pdf internals