I use opera. Whenever I try to end writing something in italics (by clicking on the "i" button or by using ctrl+i) my text marker just jumps back to the front of the line without doing what it's supposed to do...
The same goes for bold and underline.
Then there's also the "enter leaves a blank space" thing and the copy paste and right-mouse button problems that have already been mentioned.
Now I don't want to be a little crybaby about all the changes, but the text editor is pretty much the most essential part of the game... to have the plain one simply replaced with a buggy rich one is just... irritating to say the least. I've been willing to give it a shot but in all honesty it is starting to severely piss me off that in game communication is bugged.
I've tried turning off the java script but the simple editor box is just too small now to be able to really work with.
I know you're working on this and want us to test it but if you'd just put it as optional, maybe replace the rich editor with it, I sure wouldn't mind testing things... Right now though I would just like to be able to communicate in an easy and comfortable way.