Regarding google maps: old behaviour is back And I tracked it down to (drum roll...) AdBlock Plus. It does not help to simply disable it for maps.google.com, you need to deactivate the addon completely via :dialog addons. I wonder now why it performed so well after the first start of the new firefox version. Addons were blocked. When I find time I will look if there are hints on the interwebs - or contact ABP devs.
Any e17 user seeing something out of the ordinary with notifications (ie. the popup when you download a file) ???
In my case it doesn't use the default theme.
I use some kind of addon that auto-groups tabs and colourise them, that makes it quite manageable to have a hundred or two tabs open...
I will have a look this evening. If network traffic should really be an issue here (don't believe so, as it is adblock plus that causes the slowdown), I should see it then.