src/Model/Notification.php
public function withCollapseId(CollapseId $collapseId = null): Notification
    {
        $cloned = clone $this;

        $cloned->collapseId = $collapseId;

        return $cloned;
    }
public function withCollapseId(CollapseId $collapseId = null): Notification
    {
        $cloned = clone $this;

        $cloned->collapseId = $collapseId;

        return $cloned;
    }
Set the collapse identifier

@param CollapseId|null $collapseId

@return Notification