The use case here is to help collapse permissions.
If you have these two content scripts:
{
			"css": [ "style-a.css" ],
			"matches": [ "https://*.example.com/*" ],
			"include_globs": [ "https://a.example.com/*style=a*" ],
			"run_at": "document_start"
},
{
			"css": [ "style-b.css" ],
			"matches": [ "https://*.example.com/*" ],
			"include_globs": [ "https://b.example.google.com/*style=b*" ],
			"run_at": "document_start"
}
The permissions for these content scripts would merge into *.example.com, and the permission would be a clean host permission.
Topic:
Safari & Web
SubTopic:
General
Tags: