Drupal testing framework (PHPUnit) provide 3 types of tests: UnitTest, KernelTest, FunctionalTest (JSFunctionalTest)
UnitTest : Very fast but Unit Only, without drupal.
KernelTest : Is a service test with drupal but without interfaces ans theming.

In Drupal 10, you can customize the file upload path using tokens. Tokens in Drupal are placeholders that get replaced with dynamic values when the content is being displayed or when files are uploaded.

How to run commands as root / sudo user in a docker container ?

Example : connect as root user (where php is the container name)

docker-compose exec --user=root php bash

Example with CKEditor WYSIWYG inline images field.

Also see : Create a Form with Drupal 8 using Form API

Install Docker on Linux Mint 20.3

1. Update the apt package index and install packages to allow apt to use a repository over HTTPS:

sudo apt-get update

sudo apt-get install ca-certificates curl gnupg