We deviate a bit from the original topic but the chrome issue can be fixed by changing a parameter in chrome.
If you are using chrome from a computer without touch screen you can de-activate the “Touch Event” as you don’t need it. By default it should be detecting it but for some reason it’s considered as activated even if don’t have a touch screen.
For this you need to go the flag section in chrome.
Then in this screen you can force to deactivate the “Touch events API”
Then the selection behaves normally in TM1web. I have tested it on a chrome which is only used for TM1 web and I haven’t noticed any discrepancies but this need to be fully tested.