Get the Proofscape Browser Extension#

The browser extension works in both Firefox and Chrome. It is available from Firefox Add-Ons today, and should be available in the Chrome Web Store soon! Please stay tuned!

What does the Proofscape browser extension do?#

  • PDFs from the web open automatically in the ISE

  • Dedicated on-disk PDF cache avoids repetitive downloads

Why is an extension necessary to download PDFs?#

All modern web browsers impose cross-origin restrictions. This is for your safety, but unfortunately it also hampers legitimate use cases, and prevents us from doing some nifty things that would have otherwise been possible.

When you load the Proofscape ISE, it is delivered to your browser from one domain, say pise.proofscape.org, and your browser therefore won’t let it download PDFs for you from any other domains besides that one. Unfortunately, the PDFs you want don’t usually live at pise.proofscape.org; they live at other domains like arxiv.org, projecteuclid.org, gallica.bnf.fr, or digizeitschriften.de.

Luckily, browser extensions can request targeted permissions that once again empower them to do things like download PDFs for you from selected domains, and this is exactly what the Proofsacpe browser extension does.

But PDFs from arxiv.org already open automatically without the extension?#

Yes, that’s true, but the extension is still recommended for its dedicated PDF cache.

The operators of arxiv.org have elected to serve PDFs along with a special HTTP header called Access-Control-Allow-Origin. By setting this header equal to “*” they are essentially saying, “These PDFs may be downloaded by javascript running in any page.” This is great, and hopefully other PDF providers will get on board with this practice soon. For now, most do not.

Where can I view or contribute to the source code?#