can be replicated at made up url:

/administrator/index.php?option=com_contenthistory&view=preview&layout=preview&tmpl=component&version_id=

Can you test on git clone or latest nightly? #29326 might have fixed this.

tested on e375092 and the problem remains, only difference this morning is the left menu in the popup is collapsed on load

I can't reproduce the issue. Can you enable debug and post the stack trace?

Today on 50ef84d

Installed Joomla from scratch with no crazy changes to setting, - no sample data

Logged into admin

Went straight to

http://127.0.0.1/administrator/index.php?option=com_contenthistory&view=preview&layout=preview&tmpl=component&version_id=

and replicated the error - enabled debug mode and error reporting = development and get:

$typesTable is false...

public static function prepareData(ContentHistory $table)
	{
		$object = static::decodeFields($table->version_data);
		$typesTable = Table::getInstance('Contenttype', 'Joomla\\CMS\\Table\\');
		$typeAlias = explode('.', $table->item_id);
		array_pop($typeAlias);
		$typesTable->load(array('type_alias' => implode('.', $typeAlias)));
		$formValues = static::getFormValues($object, $typesTable);
		$object = static::mergeLabels($object, $formValues);
		$object = static::hideFields($object, $typesTable);
		$object = static::processLookupFields($object, $typesTable);

		return $object;
	}

Please test PR #29692.