Uncaught TypeError: navigator.sendBeacon is not a function

In Firefox 102.11.0esr (64-bit) the dev. console F12 shows following linked error when reloading

You are also loading external elements like global.discourse-cdn.com and fonts.gstatic.com that some of my privacy extensions blocks Reason: CORS request did not succeed - HTTP | MDN it may be better if you load things from local instead of privacy invading google site and such.