I have just tested on my PC in Blender 5.0.1 and the version 1.8.4 of the add-on works. Could you verify you are using this version? Previous versions don't work with the last Blender versions due to API changes.
its easy and intuitive, just fix it for blende 5.0 please
great tool, it has helped me so much, but recently it dosent work anymore, i tried everything but the measures dosen't show up on the screen