Btw. Im pretty sure this wont get prioritized anytime soon, but maybe we should provide a warning text on Special:ElectronPdf ? “Its currently not possible to create pdfs of old revisions, here is the download for the current revision ?

Still an issue today. Which is probably Proton. I guess.

No proton is the renderer, it doesn't determine what gets rendered. That is mostly a Collection extension problem + infra.

The Proton service doesn't offer a way of specifying the revision currently, that's T213369: Make it possible to render a specific article revision with Proton. (Volunteers welcome! Low priority but should be fairly easy.)

ElectronPdfRenderer (which confusingly used to expose Proton in MediaWiki and is even more confusingly tracked under Electron-PDFs - that should probably be fixed) should probably hide the "Download as PDF" link on old revisions, for now (and should specify the revision once the dependency gets fixed).

Collection is only used for "Create a book", not "Download as PDF" (and doesn't offer any actual rendering, just passes the data to PediaPress). It also doesn't support old revisions AFAIK, but that depends on PediaPress capabilities so it's probably harder to change.

Change 620481 had a related patch set uploaded (by TheDJ; owner: TheDJ):
[mediawiki/extensions/ElectronPdfService@master] Remove Download As PDF link from old revisions

https://gerrit.wikimedia.org/r/620481

Change 620481 merged by jenkins-bot:

[mediawiki/extensions/ElectronPdfService@master] Remove Download As PDF link from old revisions

https://gerrit.wikimedia.org/r/620481