So Firefox (38.0.05) has crashed out on me (once a giant chain) a few times now. The good news is that I keep the xp but it is getting annoying now. Chrome struggles with XP (messages for XP appear a couple of minutes after the mobs have died), mobs appearing and huge lag (which can either be chain breaking or a near death experience).

So what are the alternatives/ideas for how to improve this?

Z

The lag sounds like a network problem. Are you using wireless?

Do the crashes happen when using a specific class?

Yes to wireless.

Currently only playing my warrior so couldn't say about other classes.

I'm getting this too today. Constant Firefox crashes, can't get past about a 50 chain without bombing out.

Wireless yes - solid conn to fibre broadband with no issues.
Playing a chanter messing around on an attack haste build in Nimgaul Hell. Wondering if it's all just a bit too fast

Chrome can't apparently deal (see below) so I haven't been able to test in that.

I have no crashing issues using Firefox- wired connection-, been playing a while with my Shaman with some long chains...

Firefox on a different machine appears to be ok. Had some Flash issues on the original machine after an update, is there possibly a bad interaction?

All I know for sure is that wireless is notoriously shitty and inconsistent. It's an un-shielded transmission which means it's susceptible to all sorts of environmental interference.