Found in

• Nightly 112.0a1

Affected versions

• Nightly 112.0a1
• Firefox 110.0.1
• Firefox 111.0b7

Tested platforms

• Affected platforms: Windows 10, macOS 13, Ubuntu 22.04
• Unaffected platforms: none

Preconditions

• Install the Firefox en-CA build
• Set browser.search.region to CA in about:config
• Save 1 or 2 addresses in about:preferences#privacy, Forms & Autofill section

Steps to reproduce

1. Go to https://www.burtsbees.com/
2. Add one item to cart
3. Proceed to checkout
4. Click in any eligible field and use autofill feature to preview and autofill the eligible fields

Expected result

• The eligible fields are properly highlighted when using the autofill preview and the autofill feature.

Actual result

• The eligible fields are not highlighted when using the autofill preview and the autofill feature.

Regression range

• Not a recent regression.

Additional notes

• The issue is not reproduceable in Google Chrome.

:epopescu, if you think that's a regression, could you try to find a regression range using for example mozregression?

I've retested this issue in Nightly 125.0a1 (2024-03-04) on Windows10 x64 given that Bug 1755033 has been RESOLVED FIXED.
The issue no longer persists in the latest Nightly 125.0a1 version.
As agreed with the engineering team and based on this comment, we will mark this issue as fixed and verified.