The web navigator (browser) has had "registerProtocolHandler"[1] api, which has been around since at least 2008[2]. The history has been a little complicated, but it lets one write a page that can handle addresses of this sort. That could be a handshake relay page, that loads the handshake content, then renders a page with it.
There is also similar work in WebExtensions to allow this to happen in the extension layer. Here's[3] a list of p2p-related handlers which were whitelisted (similar was done in Chrome), but "web+handshake" would work without whitelisting. These extensions would obviously be more useful if any mobile browsers had extension support. Firefox seems to have just shut the door on most extensions![4] What the hack?!
There is also similar work in WebExtensions to allow this to happen in the extension layer. Here's[3] a list of p2p-related handlers which were whitelisted (similar was done in Chrome), but "web+handshake" would work without whitelisting. These extensions would obviously be more useful if any mobile browsers had extension support. Firefox seems to have just shut the door on most extensions![4] What the hack?!
[1] https://developer.mozilla.org/en-US/docs/Web/API/Navigator/r...
[2] https://caniuse.com/mdn-api_navigator_registerprotocolhandle...
[3] https://bugzilla.mozilla.org/show_bug.cgi?id=1428446
[4] https://www.androidpolice.com/2020/09/03/firefox-update-face...