I can modify the "Accept" header in outgoing HTTP requests in Firefox 129, so it still works.

It would be nice if syntax errors in the rules would be shown.

I must report this dev cuz he is too smart :)))))) i loaded simultaneous heavy sites in 0.4 seconds per total processor time like in the old times ... Beer my friend!!?

I would greatly enjoy a switch-like header on a separate string dedicated to all that burdens loading websites, like java injections, scripts, tags, consent&comply&obey-and-give-me-all-you-have ... And after their site jumped in my Mangler boat to be able to switch and drop case for the second string thus leaving free my highway for just the website

Think about it
Nobody would know who was there or if it was as the request appeared to came from a browser ported on a cloud ... And they record solely the loss of valuable, precious d-a-t-aaa :))) and if lost then nothing happened there

Only their AI bot will enrage its crawling on the cloud for a while, but to find nothing

If this works then I'd be again at surfing speeds we had before the Facebook's wave of sympathy decline started

The idea is great. Produces no effects on Firefox 124. I've tried to remove content-security-policy header with it.

Nice!, works greatly. but I would need two things:
- able to put shortcut on bar to enable/disable the inserts
- add check per url key basis. then we could put /api/xpto/ as url key. so it would be active only when url contains this text

Example rules:
example​.com;/api/xpto/
.*regexp\d+

thank you!

I needed something to test security on a site. This was the only tool that was easy to use. I was able to verify that my changes actually were resent to the request object.

That’s a nice tool with a friendly interface (which are so rare nowadays), but it’s worth stating clearly in the description, that it is able to modify *only request* headers. (Even better — to make it possible to modify response too, of course. ;-)