1998562 - [ebay] Cannot autofill street address on "complete your account info" page

Status: NEW

(Firefox for Android :: Autofill, defect)

Description

[Matt Tighe [:matt-tighe]]

Preconditions:

Have some saved addresses.

Steps to reproduce

1. Go to: https://www.ebay.com/
2. Sign up for an account but do not add an address
3. Click "buy now" on a product
4. See page prompting to add an address
5. Focus the street address field
6. Observe the behavior.

Expected result:

The address autocomplete prompt is displayed

Actual result:

The prompt is not shown

Device information

Android device model and OS: Pixel 2 XL emulator

Comment 1

[Matt Tighe [:matt-tighe]]

Bug investigation:

We determined that nsFormfillController::ShowPopup was being called from the JS side but never completing. This was because the input referenced here is never set, which is normally done through this function. Tracing this back up to JS, we expect to call markAsAutofillField here. However, the addressFields variable here is empty, because the conditional above is triggered since there are fewer than 3 fields here.

Next steps are to investigate if/how fields are normally set as input fields in cases where the sections are below this threshold.

Comment 2

[Matt Tighe [:matt-tighe]]

Attachment: Screenshot 2025-11-05 at 3.19.13 PM.png

Comment 3

[Matt Tighe [:matt-tighe]]

Removing the conditional allows us to successfully continue through the ShowPopup code, but the prompt is still not displayed. A key down event is recognized here which works though the AutoCompleteController until it starts searches for matching fields.

When the searches complete, there are 0 results available. This means we never execute the OpenPopup call here. In the working example there are matches at this point.

Next steps will be to investigate why we fail to provide match results here. The Search Provider in this case should be the FormAutofillChild.

Some rough notes tracing this at EoD:

search here is an nsIAutoCompleteSearch. This StartSearch is defined in the nsFormFillController. This calls mFocusedPopup->StartSearch with the popup in StartControllingInput. This interface is implemented by the AutoCompleteChild. I could see breakpoints being hit up to here in the child, but then the phone screen would reset and kick me out of the devtools debugger. More tomorrow!

Comment 4

[Matt Tighe [:matt-tighe]]

Oh! Also the threshold was added in https://bugzilla.mozilla.org/show_bug.cgi?id=1304634. Might be a clue to investigate later as to why that behavior exists in the first place

Comment 5

[Matt Tighe [:matt-tighe]]

According to :dimi, this threshold was first introduced to avoid false positives and there are plans to remove the threshold.

:dimi, could you possibly share more about what kind of false positives we are looking to avoid? Is it possible we could accelerate the timeline for removing the threshold?

Comment 6

[Matt Tighe [:matt-tighe]]

For a comparison on Chrome:

they seem to recognize the field as autofillable, but give the user complete control in how to fill it. I'm able to select to fill it with logins, credit cards, or any part of an address

Comment 7

[Dimi Lee [:dimi]]

(In reply to Matt Tighe [:matt-tighe] from comment #5)

According to :dimi, this threshold was first introduced to avoid false positives and there are plans to remove the threshold.

:dimi, could you possibly share more about what kind of false positives we are looking to avoid? Is it possible we could accelerate the timeline for removing the threshold?

Not a specific false-positive, but in general avoid showing popup as long as a field matches any of the keyword listed in here.

As for the timeline, we do plan to implement this early next year. If the time doesn't work for the mobile team, let's chat offline to see if there is anything we can do.

Comment 8

[Matt Tighe [:matt-tighe]]

I don't think there's a huge rush on our end. I may continue investigating the issue I found here with the search provider, but otherwise I have added this to bug 2000036 and we can take another look at it down the line.

Comment 9

[Neil Deakin]

I plan on adding support for autofilling less than 3 fields when one of the fields has an autocomplete attribute in bug 1930874.