Qt UI: small code refactoring (step 1)
Qt UI: small code refactoring (step 2)
Daemon: small code refactoring (step 1)
Daemon: small code refactoring (step 2)
Gtk UI: small code refactoring (step 1)
Gtk UI: small code refactoring (step 2)
Gtk UI: small code refactoring (step 3)
Gtk UI: small code refactoring (step 4)
Qt UI: small code refactoring (step 3)