A portable application can be run from a removable drive (USB flash drive, iPod, portable hard drive, etc) on any Windows computer without installation. You will carry the program with settings on removable drive and don't modify settings on host computer. On Vista and above turn off User Account Control (UAC) or run launcher as admin.
The browser that puts you in control without installation. Download Portable Vivaldi stable Online (0.8 MB) 21/06/19 In first screen enter: 6.2.3105.43 or 1.0.435.46 for XP/Vista Download Portable Vivaldi snapshot Online (0.8 MB) 21/06/19 In first screen enter: 6.3.3119.4
Extract and run VivaldiPortable or VivaldiSnapshotPortable (stable and snapshot have their own folders and settings). Settings of installed Vivaldi should be preserved.