Aloha Dave!

Those sound really suspicious. I guess the question is why are you seeing those now: is it some website you are visiting that promotes junk software, or did something get installed to your system already?

One possible culprit would be an extension. You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

• Command+Shift+a (Windows: Ctrl+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. Then cast a critical eye over the list on the right side. All extensions are optional. If in doubt, disable.

Often a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step.

Any improvement?

And run a general malware sweep with the following or a similar program:

https://www.malwarebytes.org/antimalware/mac/

Malware-specific support forums can be found listed in our support article: Troubleshoot Firefox issues caused by malware.

Can you get rid of it?

. Whenever you get a message / popup that software / files need to be updated;

DO NOT USE ANY OF THE PROVIDED LINKS

While this may be a legitimate message, it could also be Malware or a Virus. Anytime you want or need to check for upgrades, go to the website of the True Owner of the program in question. For example, to check out Firefox, go to https://www.mozilla.org {web link}

You can report such a site at; Google Report Phishing Page {web link} which is the same when done while on site by going to Help > Report Web Forgery

Help us safeguard Mozilla’s trademarks by reporting misuse {web link}

For the last eight months, an epidemic of Fake Update Notices have been popping up all over the place. https://support.mozilla.org/en-US/kb/i-found-fake-firefox-update