Hi, If you have Tracking Protection enabled, try turning it off: 3-bar menu > Options > Privacy & Security > Tracking Protection. If that isn't it, try this on one site and if it works do it on the other one as well: Delete ALL references to the website in question. To do that, open the 3-bar menu > Library > History, then click the Show All History link at the bottom of the list to open the History-library window. Search for the website you want to clear by typing its name in the Search History field in the top-right corner, then press Enter. Now in the search results, right-click on the site you want to remove, and select Forget About This Site. (Browsing and download history, cookies, cache, active logins, passwords, saved form data, exceptions for cookies, images and pop-ups for that site will be removed). Give it a minute to complete the deletion, then try the site (not from an old bookmark) again. More - [[Delete browsing, search and download history on Firefox]] If that doesn't help, type '''about:config''' into the address bar, press Enter, accept the warning, scroll down the alphabetical list and see if '''general.useragent.override''' exists. If it doesn't just close the tab - it wasn't that! If it does exist, then right click > Reset, close the tab and restart Firefox. Now try the sites again. ''If your question is resolved by this or another answer, please take a minute to let us know. Thank you!''