Did you check the settings in Options/Preferences for Forms & Autofill and history  ?

• Options/Preferences -> Privacy & Security
  Firefox will: "Use custom settings for history" -> "Remember form and search history"

You can use these steps to remove saved items from an autocomplete drop-down list.

1. click the (empty) input field on the web page to open the drop-down list
2. highlight an entry in the drop-down list with cursor Down key
   do not click the mouse or press the Enter key
3. press the Delete key (on Mac: Shift+Delete) to delete the highlighted entry

Note that hovering with the mouse no longer works.

Yes I had it set to Remember form and search history. I turned it off, exited and restarted Firefox and that fixed the problem. Thank you

12/17: The problem is back, I did not change any settings and the privacy settings box for "Remember search and form history" is still unchecked. Firefox continues to save every name I type as a saved address. Any other ideas on how to turn this off?

Glenno said

Yes I had it set to Remember form and search history. I turned it off, exited and restarted Firefox and that fixed the problem. Thank you

Would you be so kind as to mark cor-el's post as Chosen Solution ? ('Solved the problem' button to the right)

Thank you in advance  !

12/17: The problem is back, I did not change any settings and the privacy settings box for "Remember search and form history" is still unchecked. Firefox continues to save every name I type as a saved address. Any other ideas on how to turn this off? Anytime I type any name into any form in any website, Firefox adds it to my saved addresses. Shouldn't this be a option and not an automated thing?

If this only happens with addresses then this is likely the settings under Forms & Autofill. When this feature is enabled then Firefox will save addresses automatically. You can inspect and edit and remove stored addresses, but as long as this feature is enabled addresses will be stored. There is no block exception possible as far as I know.

• https://support.mozilla.org/en-US/kb/automatically-fill-address-and-credit-cards

Thank you Cor-el, but even when I had it turned off it was saving names and addresses of people that I searched for in my cloud database.. It would be nice if firefox had an option to "ask before saving" or a "don't add new addresses" setting. I will have to delete the new addresses daily until it is fixed or, I may use another browser just for this and keep firefox for everything else.

Do these addresses show if you click "Saved Addresses" in "Options/Preferences -> Forms & Autofill" ?

Yes, normally I have 2 saved address (one for personal and one for work).

This person is exactly correct. In order for this forms filling feature to be taken seriously, there needs to be a way to allow form filling, but disallow new entries from being saved. Firefox automatically creating endless entries is not useful and more so, keeps me from using the feature entirely.

Most users I would imagine are going to have 1 - 3 entries for their personal information they want saved for forms use and that's all.

I feel like something has changed in perhaps the past few months. The current Firefox (MacOS for me) has simply a check box for "Autofill addresses". If it's on, it not only auto fills, but now stores every single thing you're entering in forms; it's quite obnoxious given it presents you with the choice at form submit time of either "update existing address" or store new, you cannot choose no Firefox, don't store the f'ing form I just filled since it has no relevance.

I've had to turn the checkbox off since any given day will see my addresses increase by several, making the feature completely useless. There was some period of time where I feel like it used to have more granular options where you could store, or pre-create, addresses you'd like to use for autofill, but otherwise never prompt or auto store anything new.

I switched to chrome (reluctantly). If Firefox can fix this I'd be back in a jiffy