When posting or replying, in the text box, my cursor is flashing on an off in a somewhat syncopated rythmn instead holding solid.  Further and more importantly, when I begin to type and fill the text box below what is initially visible, the screen keeps scrolling up after I type.  I can't keep the line I'm typing on displayed.  I have to scroll down to find my last line and as I type the text line jumps up and down.
I have no idea what may be causing this and it does not occur anywhere else on my system when I'm typing in anything else.  Otherwise I would think a malware macro was causing this, but as I just lost my hard drive last week and installed a new one, reloading everything from scratch, I think I have a clean machine.   This problem has occured contineously for the past week since reloading AH and getting back on the Forum.