@griffi-gh Do you have any policies set? If so, this is because of bug 2038282 ( https://bugzilla.mozilla.org/show_bug.cgi?id=2038282 ), and you should set the DefaultSerialGuardSetting policy to 3 to enable WebSerial.
We're happy to announce that Firefox 151 (shipping now!) has support for Web Serial! There's a bit more information here: https://blog.mozilla.org/en/firefox/firefox-web-serial-adafruit/
As always, feel free to report problems here or by filing a bug...
@griffi-gh @Tyeth Thanks for those examples! We have confirmed that some devices will work over Bluetooth, but we also know that Chrome does some additional things to make more devices work that we haven't implemented. There's more information at bug...
