Drupal 8

1. Update drupal core and contrib odules to the last version
Example with composer if you use core-recommended:
composer update  drupal/core-recommended:9.3.14 -W

2. Perform Regular Backups of the files and database.
You can use Backup and Migrate module

Draggable table Form Example

Step 1 : Form build

Example: settings for local environnement.
Create the local settings file : local.services.yml the add to local settings.php file

# Local service config
$settings['container_yamls'][] = DRUPAL_ROOT . '/sites/default/local.services.yml';

Step 1 : Add the package cweagans/composer-patches
composer require cweagans/composer-patches

Doc : https://www.drupal.org/docs/drupal-apis/form-api/conditional-form-fields

States that can be applied to a form field element:

Add following packages to composer.json file next to drupal repository

PHP Class using StringTranslationTrait

StringTranslationTrait allow to get t() and formatPlural() methods
Example:
use Drupal\Core\StringTranslation\StringTranslationTrait;
use Drupal\Core\StringTranslation\TranslationInterface;
class MyClass {


State servic eallow to store variables such as state of the server temporarily or permanently

Examples:

Drupal settings file can contains variable which can use to use for different configuration in different environments.

Example:
env_name
default_info_nid

$settings['env_name'] = 'Local';
$settings['default_info_nid'] = 1';

You can use IMCE to select a file.