Did you just run into a download or a file on your computer that has a digital signature from Vivaldi Technologies AS? If so, please read on.
You will probably see Vivaldi Technologies AS when clicking to run the file. The publisher name is displayed as the "Verified publisher" in the UAC dialog as the screengrab shows:

You can view the additional details from the Vivaldi Technologies AS digital signature with the following procedure:
Here is a screenshot of a file that has been digitally signed by Vivaldi Technologies AS:

As you can see in the screenshot above, Windows reports that "This digital signature is OK". This implies that the file has been published by Vivaldi Technologies AS and that no one has tampered with the file.
If you click the View Certificate button shown in the screenshot above, you can examine all the details of the certificate, such as when it was issued, who issued the certificate, how long it is valid, and so on. You can also view the address for Vivaldi Technologies AS, such as the street name, city and country.
DigiCert EV Code Signing CA (SHA2) has issued the Vivaldi Technologies AS certificates. You can also see the details of the issuer by clicking the View Certificate button shown in the screenshot above.
The following are the Vivaldi Technologies AS files I've gathered, thanks to the FreeFixer users.
| Detection Ratio | File Name |
|---|---|
| 0/66 | vivaldi.exe |
| 0/60 | vivaldi.exe |
| 0/61 | vivaldi.exe |
| 0/73 | vivaldi.exe |
| 0/73 | update_notifier.exe |
| 0/71 | update_notifier.exe |
| 0/58 | vivaldi.exe |
| 0/58 | vivaldi.exe |
| 0/62 | vivaldi.exe |
| 0/65 | vivaldi.exe |
The detection percentage is based on that I've gathered 1122 scan reports for the Vivaldi Technologies AS files. 0 of these scan results came up with some sort of detection. If you like, you can review the full details of the scan reports by examining the files listed above.
The analysis has been done on certificates with the following serial numbers: