Mozilla/5.0 (X11; Linux i686; rv:38.0) Gecko/20100101 Thunderbird/38.8.0
I have recently been running into what appears to be a new display bug
with emacs-25 on an xterm display and just now got around to filing a
bug report (Bug#23819). Dunno how to fix it offhand, or even to
reproduce it reliably alas (perhaps someone with tty display expertise
can look into it?). It'd be nice if Emacs 25 didn't have this
regression, as it's confusing when the display gets trashed.