TYPO3 Core

Regards BE Module: User admin
I have tried to switch the language settings for a beuser, setting is saved. But the language labels do not change in the Backend.

I have noticed that,
- if the uc field (be_users) in the database is empty, the chosen setting if stored in the serialized array.
- if the uc field (be_users) contains user settings in as a serialized array, the system does not update/change the BE lang setting anymore. Emptying the field enables the save again.

In the function backendSetUC (class.t3lib_beuserauth.php) the function call to writeUC does not get triggered anymore.

I added:
if($this->user['lang'] != $this->uc['lang']){
$this->uc['lang']=$this->user['lang'];
$U=1;
}

Which makes the proces work again.

(issue imported from #M14196)