Saving matrix field of a duplicate of an entry not working

Question

I'm creating a cron job to automatically import new entries (vacancies).
I have an entry that I use as a template with some standard data fields and matrix fields. If it's an entry that has not been imported before I create a new entry as a duplicate of the template entry.

$entry = Craft::$app->getElements()->duplicateElement($entryTemplate);

The template already has the matrix blocks but only placeholder data that I want to overwrite like this:

// existing matrix fields (already created or from template)
$matrixBlocks = $entry->myMatrixBlock;

/** @var MatrixBlock $matrixBlock */
foreach($matrixBlocks as $matrixBlock) {
    $matrixBlock->setFieldValues(['contactText' => 'random text']);

    $success = Craft::$app->elements->saveElement($matrixBlock);
}

The strange thing is that the ownerId of the matrixBlock isn't the value of the $entry->id nor is it the value of the template id. It generated a new ownerId. It works correctly when I import it a second time because the owner id is now correct.

Answer 1

This sounds suspiciously like a bug that was fixed in today's Craft 3.6.10 release.

Fixed a bug where entries could return the wrong Matrix/Neo/Super Table blocks if the blocks were queried immediately after the entry was created via craft\services\Elements::duplicateElement().

My guess is if you update to that release, it'll behave like you expect now.