Didn't work. I installed it, then reloaded my local page (file://yadda yadda). CORS is still blocked. Tried the test page and I get: CORS is blocked for GET ✖ So either the extension doesn't work or it's too complicated to use. My steps: Install > Enable extension > Go to my page > Add to white list > Refresh and test > Go to test page ...so yeah, I'm giving up. If this thing is supposed to work then it needs better UX.
Allow CORS: Access-Control-Allow-Origin plugin allows easy addition of (Access-Control-Allow-Origin: *) rule to the response header, enabling cross-domain Ajax requests in web applications
It unblocks the CORS feature, which is blocked by default in modern browsers, and provides a toggle button for activation