The most basic functionality doesn't work anymore. I added the exact domain and pointer to the exact one file to watch. I opened the file in another tab and could see that it changed, but the extension did not reload the page.

Plugin did not work for me. (Updating review for developer notes)

Notes for developer: Windows 10 Pro, v1703. Firefox 57.0.2 64-bit. Installed add-ons: Adblock Plus, Greasemonkey, LastPass, uBlock (not sure why I have two Adblockers installed, but whatever) Web Developer, Plugins: OpenH264 Video Codec, Widevine Content Decryption, Shockwave Flash. Steps to recreate: Installed add-on, enabled and disabled auto reload a few times to get it to work (did not work on first install), completely closed and restarted browser, repeated steps of cycling the auto reload toggle, tried going into advanced options to see if there was a missing setting and there didn't appear to be one. This was tested on a local file. File was saved using JetBrains Webstorm (not that it should matter, but it may be worth noting). I was NOT using the Webstorm web server. Again, this was accessing the HTML file as a local file directly through the browser.