This began two weeks ago. I use an up-to-date Firefox browser (38.0.1) on Windows 7. Two weeks ago I opened an email from a friend that was Rich Text formatted rather than plain text. I clicked reply, and then clicked the Plain Text button. But there was no cursor that would let me type in my reply. I couldn't paste anything into the reply box either. I restarted Firefox. No go. I restarted my computer. No go. Cleared Cache and Cookies. No go. What I *can* do -- and the only way I now have to reply to messages -- is to click on any email (rich text or plain) -- click reply, then click the Rich Format button. This then allows me to type or copy/paste, and *then* I have to click Plain Text again in order to send a Plain Text email. I hate Rich Format and never use it. Friends (mostly) know to send me email only in Plain Text, but up until two weeks ago it didn't matter. I just clicked reply to any email and typed in the reply box. Now, that's impossible - though Chrome, IE and any browser on my cell works just fine - so this is clearly a Firefox issue. Why is this happening and can anything be done to fix it?