Alx Knife by Dormines

Matching of hosts is done with either simple strings or regular expressions.
Rules can have multiple headers apply to multiple hosts, or simply insert a single header for a single host.

Insert rules in the the first textarea in option.

Example:

example​.com
.*regexp\d+
# This is a comment.
X-Forwarded-For=192.168.1.10


Script to inject on load page:
Insert script in the the second textarea in option.
Example:

if(document.location.host==="www.mozilla.org"){
alert("OK");
}