Thanks for the holler. osx 11.1, latest update to LR. Was getting a 'beep' as if the action wasnt allowed. I have since restarted the program and it has seemed to be resolved. However I will leave this open as it has happened before so will report back once problem starts again.
In addition to answering Johan's questions: Beware that while in Loupe mode, the Paste Settings command only pastes the settings to the most-selected photo, not to the other selected photos. Workarounds to this confusing design feature: Right-click the selected photos in the filmstrip and do Develop Settings > Paste Settings, or use the Sync Settings button in the lower-right.
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