great big list of stuff that only fully works in IE here: https://docs.microsoft.com/en-us/sharepoint/install/browser-...
https://docs.microsoft.com/en-us/microsoft-edge/deploy/emie-...
So an ActiveX control written in 1996 can run in Windows 10 Enterprise today via IE11. Neat... I guess.
It's crazy that modern sharepoint version still use ActiveX for something like this imo. I wonder if Microsoft's newer web APIs could be used to reimplinent this functionality without ActiveX