GMail makes a large number of XHR requests, several per second. uMatrix counts them all, which leads to a very noticeable and annoying delay of several seconds while typing between the moment a key is pressed and when it appears on the screen.

Disabling uMatrix even for the entire site makes no difference, since it continues counting the XHR requests even when disabled.

Please change it to not count requests when it has been disabled for a site, or to have the option of disabling the counts for certain domains or grid squares.