@DatasourceType("anchorsDatasource")
public class AnchorLinkSelectFieldSupport extends OptionSelectFieldSupport {

    private final LinkService linkService;

    @Inject
    public AnchorLinkSelectFieldSupport(final FieldDefinition fieldDefinition, final OptionListDefinition optionListDefinition, final LinkService linkService) {
        super(fieldDefinition, optionListDefinition);
        this.linkService = linkService;
    }

    @Override
    public DataProvider<Option, ?> getDataProvider() {
        final var noneOption = new Option();
        noneOption.setValue("");
        noneOption.setLabel("None");

        // one may use a set of hard coded items to reproduce this issue
        final var options = Stream.concat(
            Stream.of(noneOption),
            linkService.getAnchorsDefinedInPage(null).stream()
                .map(anchor -> OptionUtil.of(anchor, anchor))
        );

        return DataProvider.fromStream(options);
    }
}

<components>
    <id>datasource-anchors</id>
    <component>
        <type>info.magnolia.ui.field.SelectFieldSupport</type>
        <implementation>my.project.dialog.field.AnchorLinkSelectFieldSupport</implementation>
    </component>
</components>

anchorTarget:
  label: fields.anchorTarget
  $type: comboBoxField
  datasource:
    name: anchors