Will the command dconf reset -f / remove data from the hard disk where I've installed Ubuntu?
2 Answers
Short answer:
Many applications store their settings (in binary format) in the dconf database. Also many interface settings are done by editing this database.
This "data" will be lost if you run the command you mention, and all settings inside the database will go back to default. Your data, as in the files and folders you created, have nothing to do with the dconf database, and will remain as they are.
This command resets all of your user configuration settings to the factory defaults. It will not remove any files from your drive.