Are you logged into your Firefox account and syncing? It is possible to sync custom preferences so if you are logged in it's possible you're syncing previous changes you made to about:config.

could be, but that doesn't make sense since its a new profile... why would another profiles settings sync with a new profile?? also, i just get the logic as to why I can't just hit a reset or "refresh" button and RESET settings lol instead of loading the old settings. its an absolute buggy mess. I can literally see it loading the old settings is about:config with the "only show modified settings" ticked. it wont stop loading those stupid settings. I'm about ready to abandon firefox altogether cause it all started when my profile became corrupted after an update and wouldn't start firefox at all, and after the "refresh" it just loads my old profiles settings. it seems like a huge security flaw imo, but i don't know for sure. just frustrated i can't just hit "reset" and have it actually reset like its supposed to.

Hello

Firefox Sync syncs the data associated with your Mozilla Account, and every profile you sign into that account will download and merge that synchronized data. When you sign up for Sync, all your synchronized data is uploaded to and stored on the Mozilla server. All devices or profiles logged into that one account are considered "connected devices." The profile is the local folder on your computer that stores all your unique settings and data.

When you create a new local profile and then sign into your Mozilla Account, the Sync downloads the data from the cloud and merges it with the local profile data.

So

Your original profile had unwanted settings. When you create a new local profile and then sign into your Firefox Account, your data is downloaded into your new profile file.

If you want to delete that data you must delete your account (like RESET), you can do so by clicking the Delete account button at the bottom of your account settings page. For detailed instructions, check out How do I delete my Mozilla account?

Warning: This process will delete your synced data (bookmarks, passwords, history, etc.) from the server.

Mozilla account - Managing account data Delete sync data from Firefox by signing out of your Mozilla account

I believe you can also clear your data from the sync server by resetting your password using the forget password option. This will clear out your bookmarks and passwords from the server too, of course, so you'd want to back those up manually on your hard drive first as well.