You can check this pref on the about:config page.

• extensions.formautofill.creditCards.enabled = true

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

• https://support.mozilla.org/en-US/kb/about-config-editor-firefox

I did and restarted Firefox, to be sure. It did not work. Still does not show it.

When you say it does not show it, do you mean on the Options Preferences page? I guess that would be useful to use the button!

Try changing the following preference to true:

extensions.formautofill.creditCards.available

Sorry, Linux has Preferences, not Options.

Thank you jscher2000 extensions.formautofill.creditCards.available did the trick for me. The option now appears on the Firefox Preferences.

I am having the same problem. But I found that the extensions.formautofill.creditCards.hideui was true. Changing it to False fixed the problem.

I don’t have a ‘Preferences’ under the main menu.....

I don’t have a ‘Preferences’ under the main menu.....

If you are on Windows, look for Options (Microsoft and other OS makers don't agree on what to call it).

I notice a Normandy pref that apparently sets extensions.formautofill.creditCards.hideui = false to show this section.

• app.normandy.startupRolloutPrefs.extensions.formautofill.creditCards.hideui = false

In Firefox go to Options/Privacy and Security/Forms and Autofill. You should see a checkbox to autofill credit cards.If you don't then follow the instructions above to make extensions.formautofill.creditCards.hideui false.

More prefs you can check:

• extensions.formautofill.available = `on` (String) (if `detect` isn't working)
• extensions.formautofill.creditCards.available = true (Boolean)
• extensions.formautofill.creditCards.enabled = true (Boolean)
• extensions.formautofill.creditCards.hideui = false (Boolean)