1. In the Location bar, type about:config and press Enter. The about:config "This might void your warranty!" warning page may appear.
2. Click I'll be careful, I promise!, to continue to the about:config page.
3. In the bar above type in browser.newtab.url
4. Right click the first result and select Reset

• Remove a toolbar that has taken over your Firefox search or home page

Thanks for the careful instructions and your time. I did everything and it worked perfectly right up to the "right click and select Reset". The Reset isn't in bold, so I can't select it. Now what?

you can also try the search reset addon

• https://addons.mozilla.org/en-us/firefox/addon/searchreset/

do note

• it will also reset your homepage and search (back to google)

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Firefox/Tools > Add-ons > Appearance).

• Do NOT click the Reset button on the Safe Mode start window or otherwise make changes.

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

Does anything come up if you search for that site on the about:config page?

cor-el, nothing popped out at me in safemode and I couldn't find anything by searching about:config.

I'll probably just reset the browser settings when I get annoyed enough.

Thanks for both your help. :-)