Module development and code questions

Error: Class "Drupal\ctools\ParamConverter\TempstoreConverter" not found in Drupal\Component\DependencyInjection\Container->createService() (line 262 of core/lib/Drupal/Component/DependencyInjection/Container.php).

For a customer I created a content_type and failed to create it with the "Display settings" attribute. That is key if this content_type was going to have the Authored on, Authored by field on the node edit form.

I could not find a way to retroactively add that back in so I recreated the content_type and migrated the old content into it. Of course, the node's created timestamp will be on the same date and close to the seconds and if I want to sort they will order by the new creation timestamp, often for the same minute.

Hi, I don't know if I'm Off topic if so I apologize in advance.
I have 2 arrays that I feed with employee codes.
$aDipe contains all employees
$aDipeA contains the dependent codes that cannot work
Currently the array is made up as follows:

$aDipe[$dipeID]['id'] 	    = $dipeID ;
     $aDipeA[$dipeID]['id'] = $dipeID ;
            array_diff($aDipe, $aDipeA) ;

And it works well

Hi Drupal Community, I hope this is the right place to posting this question.

Hello, I want to write a custom module for flags. It should perform some actions, if a user flagged a user and the user who's got flagged, already flagged the flagging user. You know?

I found this snippet, but I really don't know, how I can get this to work. Is it possible to get this done? And if so, how I can get the user who's flagged and check if he has also flagged the other user?

Snippet:

<?php

Related to this post for some reason customer's theme appears to be mishandling the single foot mark (') which most refer to as apostrophe and at the twig.engine stage is outputiting the html of