Multiple tab processes (aka "e10s-multi") should be shipping in Firefox 54 (now in the Firefox Nightly channel). The initial rollout of multi-process Firefox ("e10s") had one process for the browser UI and one process for all tabs (and a separate process for sandboxing Flash), so one bad tab could lock up all your tabs but your browser UI would still be responsive so you could close the bad tab. e10s-multi will increase the number of shared tab processes to two or more, balancing tab isolation vs memory overhead.

In the meantime, you can test more tab processes by increasing the "dom.ipc.processCount" pref in about:config. I set my process count limit to 999. :)

I had a look a week or so ago at e10s, but it seemed that because my laptop was a touch screen laptop (Dell XPS 13) the feature was disabled.

The UI said it was due to accessibility features.

Is there a timeline for getting it working with touch screens or has that already happened?

I've heard a lot of people say that, but I'm still having problems with a single tab locking up the whole browser for 5-40 seconds on FF 53.0a2 Dev Edition with e10 and process count at 999.

Hmm… I'd look but there don't seem to be any builds since late November on mozilla.debian.net.

While that's theoretically true, I've never switched from Firefox as my daily driver and crashes are very rare in my experience (more common on mobile, but I leave a bunch of stuff open there as well). Furthermore, when it does crash the session restore does a pretty solid job of restoring and letting me easily exclude tabs from being restored.