Download Extension Admin Block

A simple extension that allows administrators to stop downloading files that have certain extensions.
The extensions to be blocked are retrieved from the registry key:
[Computer\HKEY_CURRENT_USER\Software\Policies\Google\Chrome\3rdparty\Extensions\fclpdmhgmmdocfbbomojkpngpffjhnjl\policy]
"BLOCKED_EXT"="exe,msi,ecc" // comma is the separation character
It is obviously possible to distribute the registry key via Group Policy.
To make this extension mandatory, distribute the chrome admx policy templates.