From the upstream policykit bug entry, it is actually a misuse of the policykit API from brltty. I have uploaded a fix in Debian's brltty 5.6-5.
Ubuntu should definitely include the policykit-fix patch contained in that 5.6-5 version as an update to ubuntu 18.04, otherwise all blind users will have the issue, thus unable to use the graphical desktop.
From the upstream policykit bug entry, it is actually a misuse of the policykit API from brltty. I have uploaded a fix in Debian's brltty 5.6-5.
Ubuntu should definitely include the policykit-fix patch contained in that 5.6-5 version as an update to ubuntu 18.04, otherwise all blind users will have the issue, thus unable to use the graphical desktop.