Cocoa-AppleScript Applet allow open links type chromie://{path_on_filesystem} for OSX by registering a new CFBundleURLTypes based on CFBundleURLSchemes chromie
Build process
Save app & edit .plist
<key>CFBundleURLTypes</key>
<array>
<dict>
<key>CFBundleURLName</key>
<string>Chromie</string>
<key>CFBundleURLSchemes</key>
<array>
<string>chromie</string>
</array>
</dict>
</array>
Copy the app in the Applications folder
Permissions
Allow access to the app from Preferences>Security>Confidentiality