To add application-level JavaScript files to an extension, create a global/ directory in the extension’s root folder:
<extension-name> : The root folder of your extension ext.json global/ <application-level-module-1>.js <application-level-module-2>.js <application-level-module-n>.js
Place any application-level JavaScript files in this global/ directory. There is no limit to the number of files you can place in the global/ directory but the files themselves must follow these rules:
They must be anonymous, that is, have no package name defined in the module.
Structurally, they must be valid RequireJS modules.
Each filename must be unique. If a file with the same name has been loaded in another extension, an error is returned.

