This page has steps to remove this malware from your system. You will want to follow the steps for your operating system as well as the Firefox steps.

For more information about the Firefox steps, please see Disable or remove Add-ons.

Hope this helps.

This did not work for me. When searching in Firefox part of the displayed response URL includes Akamaihd.net briefly BEFORE it is replaced with a legitimate URL. I had to take a picture to record this example when I ran a serch for "sistine chapel":

4098508-a.akamaihd.net/s?q=sistine+chapel&_pg=01A52DEF-BCBB-5216-8F4F-3E35D0E8EF6A.

This was quickly replaced by the real URL https://search.yahoo.com/yhs/search?hspart=Lkry&hsimp=yhs-SF01&ts=sy&type=ANYS_A0RU0_set_bfr&obt9bpdyed=0&p=sistine+chapel&param1=na3P9yVrJGqvPvD-U0GEZlnlDu3pSk5u0fJTChqj_xvVkDMviBI0Zmzs_9aCC6EDOnlIojebo7kV0Yx5SuQiIMUxMOKMV1Lbx-2ODpQHSz7uklflQNH7ejVaULuYjOv1VzJUYJ00RWk0ql_HDqf12GMPdgkv1RLdmLs6vJM-YmuOKOu8PrjqXPtLJws0wWD1qrvcwQ3n6Pyz0p0pERvGLsmckwWRUIsQqrQ0mBiDmw%2c%2c

There are a number of Akamaihd.net removal tools listed on the web, but I don't know which are legitimate. Thanks for your help!

The 01A52DEF-BCBB-5216-8F4F-3E35D0E8EF6A part of that link that you provided looks like of like an extension ID.

Enter about:debugging in your Firefox address bar. On that page, select This Firefox from the left sidebar. Seen if the Extension ID or Internal UUID of any of your installed add-ons matches that number.

If you find one that matches, go to the about:addons page and try disabling that add-on. Then restart Firefox and see if the issue goes away.

Of course, I'd still recommend scanning for malware on your system. Malwarebytes for Mac is a popular and trusted software for this type of task. It has a huge database of malware to look for, so it should find this.

Hope this helps.

Thank you for your help! Unfortunately, your last instructions did not help with my problem. I've never had a Mac virus before, and this must be a bad one. I have scanned my Mac with Malwarebytes, found 5 hits and removed them. That did not take care of my Firefox's Akamaihd.net problem. I then removed Firefox and reinstalled it. Again, when I searched for "Sistine Chapel" (or barn or any other search), the search4098508-a.akamaihd.net/s?q=sistine+chapel&_pg=01A52DEF-BCBB-5216-8F4F-3E35D0E8EF6A URL (or for a "barn" search I got search4098508-a.akamaihd.net/s?q=barn&_pg=01A52DEF-BCBB-5216-8F4F-3E35D0E8EF6A) flashes briefly before switching to a legitimate search result. But this only happens the FIRST TIME I open a new Firefox tab and search. After the first search in a new tab it does not happen when I run a new search on that tab. This does not happen with Safari! And I still find no new threats when I rerun Malwarebytes. Any help will be appreciated!

PS: There are a lot of programs listed on the web for removing Akamaihd virus on a Mac. Are any of them legitimate?

Does this happen when you run Firefox in Safe Mode?