What browser are you using? With Chrome you go to settings/advanced/language to turn spellcheck on/off. There's probably something similar in other browsers. If that doesn't work, here's a video that might help.
https://www.youtube.com/watch?v=E5Ng8fLu3Oo
I just spent a ton of time today trying to figure out why the recently visited sites thumbnails are suddenly missing from Chrome on my computer. I finally found the answer. If anyone else is having the problem I can help. Wouldn't it be nice if the software products we use were more stable? I didn't do anything to cause the loss of the thumbnails, and you probably didn't do anything to cause the loss of spellcheck.