Improve untrusted package install docs

doc/faqs/how-to-install-untrusted-packages-safely.md

@@ -3,7 +3,9 @@
 Certain Composer commands, including `exec`, `install`, and `update` allow third party code to
 execute on your system. This is from its "plugins" and "scripts" features. Plugins and scripts have
 full access to the user account which runs Composer. For this reason, it is strongly advised to
-**avoid running Composer as super-user/root**.
+**avoid running Composer as super-user/root**. All commands also dispatch events which can be
+caught by plugins so unless explicitly disabled installed plugins will be loaded/executed by **every**
+Composer command.
 
 You can disable plugins and scripts during package installation or updates with the following
 syntax so only Composer's code, and no third party code, will execute:
@@ -13,10 +15,11 @@ php composer.phar install --no-plugins --no-scripts ...
 php composer.phar update --no-plugins --no-scripts ...
 ```
 
-The `exec` command will always run third party code as the user which runs `composer`.
+Depending on the operating system we have seen cases where it is possible to trigger execution
+of files in the repository using specially crafted `composer.json`. So in general if you do want
+to install untrusted dependencies you should sandbox them completely in a container or equivalent.
 
-In some cases, like in CI systems or such where you want to install untrusted dependencies, the
-safest way to do it is to run the above command.
+Also note that the `exec` command will always run third party code as the user which runs `composer`.
 
-See [Environment variable - COMPOSER_ALLOW_SUPERUSER](../03-cli.md#composer-allow-superuser) 
+See [Environment variable - COMPOSER_ALLOW_SUPERUSER](../03-cli.md#composer-allow-superuser)
 for more info on how to disable warning