Where can I find information or read about the mechanism for installing extensions in the browser, how are they launched by the browser and similar browser mechanisms?

Question

Google Chrome

Or whatever these mechanisms are called technically.

Answer 1

You can read what extensions are and how they are installed in different browsers here
. Extensions themselves are simple code (binary files) that are downloaded and the browser can execute them. For example, extensions for chrome are put

%userprofile%\AppData\Local\Google\Chrome\User Data\Default\Extensions

Here's more details