Affected versions

• Firefox 82.0b4
• Firefox 83.0a1

Affected platforms

• macOS 10.15.7
• Windows 7

Steps to reproduce

1. Launch Firefox
2. Access about:config and set "extensions.formautofill.available=on"
3. Restart Firefox, access about:preferences#privacy and scroll to Saved Addresses...
4. Add an United States address, with valid credentials, including zip code and a phone number
5. Access Newegg and login with a valid account
6. Click on account button on the top left part of the page and select "Account Settings"
7. Now select "Payment Options" from Manage account on the right side of the page
8. Input the password as requested and click on a form (eg. Billing Address) from the Payment Options page.

Expected result

• All known forms are autofilled

Actual result

• Only Billing Address and City are autofilled

Regression range

• Will see if there is a regression.

Additional notes

• The issue can be seen in the following attachment
• Firefox 83.0a1 doesn't seem to trigger the autofill options at all.

Suggested severity

• S3

Phone Number* and State* fields were never autofilled on newegg.com , verified with Firefox 57 when Form Autofill was implemented, however the zip code field autofill worked at some point.
Managed to narrow down the regression to:

• Last good(2017-12-03): Built from https://hg.mozilla.org/mozilla-central/rev/de1f7a92e8726bdd365d4bbc5e65eaa369fbc20a
• First bad(2017-12-05): Built from https://hg.mozilla.org/mozilla-central/rev/18a9cb5cb32d0e8031d0a80901b199d5e9827d83
  Push log url: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=de1f7a92e8726bdd365d4bbc5e65eaa369fbc20a&tochange=18a9cb5cb32d0e8031d0a80901b199d5e9827d83

Changing severity to S3 because of users can still manually fill-in the other part.