tried blocking it and i do not know what to do

Hi Mary

Do you have any add-ons installed in Firefox?

Do you have a video download extension like FVD Video Downloader ?

• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

afew of them yes but i disabled all and it still did it

i was able to block the page with Ublock original

it only worked when i was in trouble shoot mode. i had shut off or disabled all extension and it still did it

I  now am ok with   ublocl ad blocker but  if  i turn it off   that site comes back Cdnsure.com

If it works in Troubleshoot Mode and in regular mode with all extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) disabled, try to find which extension is causing the problem by enabling one extension at a time until the problem reappears.

Close and restart Firefox after each change via one of these:

• "3-bar" menu button -> Exit (Power button)
• Windows: File -> Exit
• Mac: Firefox -> Quit Firefox
• Linux: File -> Quit

Can you list your installed extensions ?

• https://support.mozilla.org/en-US/kb/use-troubleshooting-information-page-fix-firefox

I d all that and i still got it with all extension disabled and also after i reinstalled Firefox there wee no extensions yet nd when i wen to any page it sill did it. Think I have it fixed now. I was able to use ublock and put it in the filter log and all good now