Intercept an HTTP request at browser end to alter some html content

Question

I would like to do as follows. What would be the best way? A general answer will also be fine.

I would like to intercept an HTTP request at the client end to alter some

Answer 1

Taken from here.

It can be done via a Layered Service Provider on Windows.

From Wikipedia:

"A Layered Service Provider (LSP) is a feature of the Microsoft Windows Winsock 2 Service Provider Interface (SPI). A Layered Service Provider is a DLL that uses Winsock APIs to insert itself into the TCP/IP stack. Once in the stack, a Layered Service Provider can intercept and modify inbound and outbound Internet traffic. It allows processing all the TCP/IP traffic taking place between the Internet and the applications that are accessing the Internet (such as a web browser, the email client, etc). "

AdMuncher for example is intercepting and inserting http code to avoid ads. Another suggestion is to find an open-source ad blocking program and see how they've implemented it.