Some improvements Rated 5 out of 5 stars
Although this works as intended, the separation between stopping out-going requests for data (stop button, XHR, etc.) and stoping in-page animations (GIF, APNG, etc.) shoul be allowed as checkbox options.
And maybe if an extra shortcut is added besides Shift+ESC (like Shift+Windows/Cmd+ESC) the ability to chose action for each shortcut, like the later only stops animations.
Anyway, thanks for the support.