fix: #3617512 \Drupal\Core\DefaultContent Exporter/Importer silently drops and cannot import 'map' field values (!16743) · Merge requests · project / drupal

Exporter.php: exportFieldItem() starts with $item->getValue() so data outside static property definitions (map fields) isn't dropped.
Importer.php: setFieldValues() resolves only known properties (including computed ones, via getProperties(TRUE)) against item_value, then uses $item->setValue(), so no per-type special-casing, and computed properties like entity-reference's entity are handled correctly.
Tests: testMapFieldRoundTrip (no properties at all) and testEntityReferenceFieldRoundTrip (compound + computed) both added to ImporterTest.php and verified against the fix.

fix: #3617512 \Drupal\Core\DefaultContent Exporter/Importer silently drops and cannot import 'map' field values