Restore Sumatra as default PDF Viewer in RStudio for RMarkdown PDF Knitting

I understand I'm late to the party as I have not updated RStudio for a long time. Now I realise that Sumatra PDF viewer is not part of the current RStudio setup anymore for viewing PDFs generated from RMarkdown knitting. I found that people talked about it here and there but haven't seen any solution. Indeed I understood that by default, RStudio wouldn't open the PDFs at all, which irritates me a lot.


  • I want to continue viewing RMarkdown knitted PDFs in Sumatra
  • immediatly & automatically opened after rendering
  • without changing my system default PDF reader (I need that to be Acrobat)

Actually, I wouldn't mind it to be another PDF viewer, however, I really loved the features of Sumatra:

  • not requiring to close files before re-rendering
  • displaying changes in real-time when rendering
  • multiple tabs possible when working on multiple RMarkdown files

As far as I see, the RStudio viewer cannot offer this behavior (no real-time view), and neither can Acrobat (would have to close file before re-rendering).

How have people adapted? This can't be just me.

(Or is this merely a sign of people using Sweave instead? Haven't tried it, but understood it allows for some synctex stuff...)

I would report this if no discussion already in the RStudio IDE github issue tracker.

Though I changed the category so that the RStudio IDE folks may jump in if they see your issue.

Thanks @cderv, I've done so.

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