Uncaught TypeError: Cannot read property 'ui.disableVehicleFetures' of null
It means attributes are null, I think. Are you sure you are using the latest official release without any modifications?
I'm using 4.8 yet, I need to upgrade.
Is possible to upgrade without afect 4.8 database?
Schema will be upgraded, but your data should be safe.
Some users is getting this error, I dont know why this mean: "Uncaught TypeError: Cannot read property 'ui.disableVehicleFetures' of null"