I tried the beta about a month ago. Made no difference to the fan problem, but it did leave a string of text in the middle of every video. I can't remember what

I tried the beta about a month ago. Made no difference to the fan problem, but it did leave a string of text in the middle of every video. I can't remember what it says as I've not got my macbook to hand but it normally disappears a few seconds after a video starts in the non-beta version.