Today in the morning I've done it again. I went to the Configuration Map Browser, right click on the "Editions and Versions" list, got by accident on the "unload" option (I actually wanted to reload another version) and released the mouse. The Version was immediately unloaded.
If a prompter would pop up to ask me "Do you really want to unload ConfigMapXyZ V1.1?" would have prevented it. Please put prompter before unloading a configmap.