This page attempts to detect uBlock origin in Chrome by probing for
chrome-extension://cjpalhdlnbpafiamejdnhcphjbkeiagm/web_accessible_resources/noop.html
and observing timing differences in comparison to a fake extension. It
should work
even if you have the extension disabled for the page.
This technique is impossible in firefox because firefox extensions'
web_accessible_resources are of the format
moz-extension://<extension-UUID>/images/my-image.png
where the extension-UUID is randomly generated for every browser instance
in order to prevent fingerprinting.