I got my first one today around 12:00 PM while I was posting in the General Discussion forum.
It has appeared about 3 or 4 times since then.
URL:http://www.gaiaonline.com/forum/general-discussion/i-am-so-screwed-pix/t.61036203_12/#12
Here is a screenshot:

I have since changed my password and gotten rid of my signature (which according to the other users may be the cause).
Threads in the GD do go very fast so I do click around quite a bit, but I do wait the allotted time between posting messages.
I went to the support page that said a highlighter add-on may be the cause but I checked both my Windows and my Firefox and neither of them has an add-on like that.
I am a very confused user right now and I am most certainly not a bot.
Any assistance would be greatly appreciated.
I really want this matter to be resolved.
EDIT: Just happened again at 2:03 PM today.
URL:http://www.gaiaonline.com/forum/general-discussion/its-really-weird-to-type-and-pee/t.61035269_17/?_gaia_t_=4614&mygntcid=613661#17