Inject and override HTTP request headers. Simply.
okayish. adds the header to ALL requests. you are not able to specidy url filters or something.
Simple and just works
Extremely simple, but it works like a charm! It's open source, too. Just make sure that when you're using it that you pay attention to main enable/disable button at the top and also in the right-click menu (otherwise it may seem like it's not working).
ShuangYa
https://modheader.com
Paul Hempshall
didierfred
https://tweak-extension.com
echo.qingwen
Vinay Kaparthi
Glenn Wilson
67726e
https://requestly.com
http://www.laobubu.net/
CAMYA