I expect this new formatted text stuff could have some bugs (I started with Mark Murphy's "RichEditText" component... and made a good bunch of changes).
If you run into an issue, please try to reproduce it with a new, small message.
Bad bug report:
"I was in the middle of typing a new message with a lot of formatted text, and it all went weird on me all of a sudden".
Good bug report:
"Enter two words, select first, change its color to red --> second word changes from default black to orange, although it wasn't supposed to".