Uninstall - easier said than done! I can not uninstall ECSP because it is running - dragging it to the trash results in an error message "Cannot remove this item because it is currently open" (or something alike). Thus I was trying to reinstall the ECSP over the running app. As I already said it results in a success, but only until restarting the computer. After that ECSP goes to the limbo again.
The only thing that changed in the configuration was the macOS update - I was not installing anything new.