When you invoke "Edit In Photoshop" from Lightroom, a background script passes the Lightroom settings on to the Camera Raw plugin (ACR), which opens the file silently into Photoshop. The ACR window does not open. There's no need, since all the settings were made in Lightroom.
There is a bug in the latest version which presents a version incompatibility message. This message should be ignored, it will still work normally.
The only way to get the ACR window is if you open a jpeg/TIFF from Lightroom into Photoshop, and you have ACR preferences set to open these file types. For raw files, the ACR window will never appear.
As D Fosse stated
The ACR window does not open. There's no need, since all the settings were made in Lightroom.
However, if you think you may want to open the ACR window, choose from Lightroom the option to Open in Photoshop as a Smart Object. Once in PS, simply double click that smart object.
Thanks for the response, very helpful