[@KingTony] I've had issues like this before, my problem was a virus/malware. I'd be typing in the window but the focus would shift elsewhere, I'd not longer be writing in the box and if I by chance hit the backspace key I'd get kicked back a page. The only thing I can suggest is try running a scan with Malwarebytes, my go-to program. It's free, and good and it even gives you a 7 day trial for the "extra" features, like real-time protection, but all you really need is the scan feature, which is 100% free.