When you go to change model units, it asks you if you want to scale your model or not. However, if you’ve made a mistake and selected microns instead of millimeters (for example), there is no CANCEL button to dismiss the dialogue box completely and not do anything. You have to go through with whatever units you chose, then revert them back when done. This is a minor issue I know, but it’s actually somewhat confusing. (I’m changing units regularly for STL printing btw). I would expect the dialogue box interaction to be consistent with the rest of the UI - the user should be able to dismiss this dialogue box and cancel the operation completely, before it changes your scene units.