The list in "Link to existing child features" does not help in selecting the right child features

[jssavola]

What is the bug or the crash?

When adding a link to an existing child feature in attribute form, the selection list element is very bare and does not contain any information to help select the right features:

Couldn't display expressions be used here as well? (See screenshot below.)

Steps to reproduce the issue

1. Configure Attributes Form for a layer that has Many to one relation with widget type Relation editor. (Screenshot 1).
2. Configure Attributes Form for another layer that is the referenced relation (widget type: Relation Reference). Add a Display expression. (Screenshot 2)
3. Go to Feature Attributes for the referencing layer and select a the referenced relation and click Link existing child feature(s) button. (Screenshot 3)
4. Observe that the selection list does not use display expression or anything identifiable. (Screenshot 4.)

Screenshot 1

Screenshot 2

Screenshot 3

Screenshot 4

Versions

3.28.4-Firenze (fd0fb72)

Supported QGIS version

• I'm running a supported QGIS version according to the roadmap.

New profile

• I tried with a new QGIS profile

Additional context

No response

[elpaso]

The list is blank because of the expression used to display the features:

You can change the display expression to suit your needs.