You are right TNE, that does work--although interestingly it runs without theming:
For reference, sudo -E btrfs-assistant-bin applies a theme and adds transparency as well.
I guess that would be thanks to the -E flag?
This kind of reminds me of way back in March when we were first hacking around on this Sway/Btrfs Assistant thing: Btrfs Assistant 1.0 is nearly here - #28 by BluishHumility