Mine works perfectly.
My plugin tweak is exactly (via copy & paste):
Code:
job_spy_notes_viewer_protocol_default_apps = {'http:': 'C:/Program Files (x86)/Microsoft/Edge/Application/msedge.exe'}
If you run in Calibre Desktop debug mode, it will show you what it received, what is wrong, and what is looks like after corrections for double-quotes for windows paths and changing the slashes.
Try running at the command line: calibre-debug -g
DaltonST