This happens when you click “run” in the modeler. Run will do a deployment to the sandbox environment. To test locally on your computer, you want to click the down arrows next to “run” and choose “run locally”
Can you please remove this counterintuitive option? After I tried to upgrade from Mendix 6.5.1 to 7.23.3 I hit run and the 7.23.3 version was committed to the repository without asking if I was sure!!!
So the upgrade was committed to the cloud! Absurd. In Mendix 6.5.1 the run localy is default. But in 7.23.3 it is default the first time!