Disable dom.battery.enabled and dom.event.clipboardevents.enabled in about:config
In about:config of TorBrowser 9.0.4
dom.battery.enabled = true
dom.event.clipboardevents.enabled = true
To avoid fingerprinting (and for privacy), why not disable them?
dom.battery.enabled = false
dom.event.clipboardevents.enabled = false
Trac:
Username: morar