I uploaded another fix just a moment ago, please try again.
You can download from the bundle's page or the single menu editor page. In both cases, itch.io fetches the plugin from my webspace, so it makes no difference for you :)
I just tested it for some time, and I can happily say it works perfectly now :D. No error, and I can open the F9 menu/toolbox. Thank you so much!
