Bugzilla

### Beta/Release Uplift Approval Request
* **User impact if declined**: In certain cases where a `ShadowRoot` is part of a form with a password field, the Password Manager autocomplete popup will not work on the password field due to an unhandled error. We estimate a small percentage of pages to be affected by this (<< 10%).
* **Is this code covered by automated tests?**: Yes
* **Has the fix been verified in Nightly?**: No
* **Needs manual test from QE?**: Yes
* **If yes, steps to reproduce**: STR are in the description for the bug (https://bugzilla.mozilla.org/show_bug.cgi?id=1634819#c0).
* **List of other uplifts needed**: None
* **Risk to taking this patch**: Low
* **Why is the change risky/not risky? (and alternatives if risky)**: This change just adds some checks to make sure that an object exists (i.e. is not `null`) before we try to access a property on it. It does not change the logic for showing the autocomplete popup.
* **String changes made/needed**:

### Beta/Release Uplift Approval Request
* **User impact if declined**: In certain cases where a `ShadowRoot` is part of a form with a password field, the Password Manager autocomplete popup will not work on the password field due to an unhandled error. We estimate a small percentage of pages to be affected by this (<< 10%).
* **Is this code covered by automated tests?**: No
* **Has the fix been verified in Nightly?**: No
* **Needs manual test from QE?**: Yes
* **If yes, steps to reproduce**: STR are in the description for the bug (https://bugzilla.mozilla.org/show_bug.cgi?id=1634819#c0).
* **List of other uplifts needed**: None
* **Risk to taking this patch**: Low
* **Why is the change risky/not risky? (and alternatives if risky)**: This change just adds some checks to make sure that an object exists (i.e. is not `null`) before we try to access a property on it. It does not change the logic for showing the autocomplete popup.
* **String changes made/needed**: