TYPO3 Core

After editing Page Properties and saving the pagetree is not showing anymore. only Reload of the Page can fix it.

I get the following Error in error.log:
Call to a member function set() on a non-object in .../typo3_src/typo3/sysext/backend/Classes/Tree/Pagetree/ExtdirectTreeCommands.php on line 370

Without investigating to much i found a Change from Version 6.2.x to 7.3-dev in Line 347 of ExtdirectTreeCommands.php

6.2.x (line 348):
$userSettings = GeneralUtility::makeInstance('TYPO3\\CMS\\Backend\\User\\ExtDirect\\BackendUserSettingsDataProvider');

7.3-dev (line 347):
$userSettingsController = GeneralUtility::makeInstance(\TYPO3\CMS\Backend\Controller\UserSettingsController::class);

in both Versions in line 370:
$userSettings->set('BackendComponents.States.' . $stateId, $state);

The new $userSettingsController imho needs this line:
$userSettingsController->process('set','BackendComponents.States.' . $stateId, $state);

I changed this line and this fixed it for me.