Hi Brenton, next time you are on the Options page, remove its address from your home page setting before closing the page. Here's what I mean:

Toward the top of the page, in the Startup section, check the Home Page field:

Look for a vertical bar character. As a simple example with short URLs:

https://mozilla.org/|about:preferences

The bar definitely can be hard to spot with long URLs, but when you find it, delete whichever of these you find --

|about:preferences
|about:preferences#general

et cetera

-- I suggest deleting the bar last so things don't accidentally get mushed together.

Firefox will save the edit when you tab out of or click away from that box. Then you can close the tab and Firefox should not open it along with your home page.

You can test by pressing Ctrl+n to launch a new window. Success?

If the problem returns the next time you exit Firefox and start it up again, we can advise on how to tackle that situation.

Thank you very much!

If you want to use the "Use Current Pages" button in "Options/Preferences > General" then you can pin the tab with the about:preferences page via the right-click context menu of the tab to prevent including about:preferences to the home page setting. You can drag the globe/padlock at the left end of the location/address bar to the toolbar Home button to set a single page as the home page.