Chrome Extensions and Match Patterns

Google Chrome is one of the most popular web browsers in the world, and Chrome extensions are small software programs that allow users to add new features and capabilities to the browser. Chrome extensions are created by developers and can be used to modify the appearance of websites, automate common tasks, and much more.

One of the key features of Chrome extensions is the ability to limit their functionality to specific websites using match patterns. Match patterns are a way to specify which URLs a browser extension should run on, and they use a wildcard syntax to match against the full URL or just a portion of it. For example, a match pattern could be set to match any URL that starts with "https://www.example.com/" or to match any URL that ends with ".pdf".

Match patterns are defined in the manifest file of a Chrome extension and are used to control access to various Chrome extension APIs. For example, a developer might use a match pattern to limit their extension to only run on Google Drive, or to run on all subdomains of a particular website.

To match all subdomains and domains of "google.com", the following match pattern can be used in the manifest file of a Chrome extension:

"*://*.google.com/*"

This match pattern uses the wildcard syntax to match any protocol (represented by "://"), followed by zero or more subdomains (represented by "."), followed by the domain "google.com", and finally, any path on the site (represented by "/*"). This match pattern will match URLs such as:

• https://www.google.com/
• https://maps.google.com/
• https://docs.google.com/
• https://drive.google.com/

and so on, for any subdomain of "google.com". However, it will not match the root domain "https://google.com". To match the root domain as well, an additional match pattern can be added:

"*://*.google.com/*",
"*://google.com/*"

This will match both subdomains of "google.com" as well as the root domain itself.

In conclusion, match patterns are an important aspect of Chrome extensions and play a crucial role in controlling the scope of an extension's functionality. By using match patterns, developers can create extensions that only run on specific pages, providing a more tailored and focused experience for users.