Facebookbug on safari

Hi

Today I tried to send a friend a link on Facebook and since he was offline, in messages. (I use Safari as browser, the new Mountain Lion OS and a MacBook Pro 13'' mid 2012)
The problem is the text which I sent with the link was pretty large, what makes the 'send' button disappear.
I can't move the window so can't find the send button, which means I cannot send this message if it is this large.
I took a screenshot to show you what I mean.
Anyone knows how to solve this?

Thank you in advance!

Lorenz

 

I'll take that as a solution, thanks!
Which is better, Chrome or Safari?