It is a failure. I am unable to work around the stupid CORs protection with addon to test code in console. The ui also needs some refinement.

Just need to be able to edit a header after is added to be 5 star plugin. For now I'll just give 3

Please add an option to edit response headers as well and export and import rules so I can replace "Header Editor", I will be watching for updates

Can't edit saved settings

Works well, but for the lack of ability to edit a rule or even copy/paste the existing fields.
The fact that you can't edit a header to fix an issue makes this plugin a pain to use.
Only acceptable (compatible) headers tool add-on for Firefox Quantum.
But it could have a better UI to manipulate the headers modification rules.
Still looking for a better implementation for Firefox Quantum.

It is too difficult to configure

Thanks for the addon but only add function works.

Tried contacting you using your website bug report but it always gives me an error after submitting.