"Vivaldi" Browser Was Installed on My PC Today. But I Did Not Install It.

It wasn't packaged with something else I installed because I didn't install anything on my Windows 10 PC today.

I only found it because MS installed an AI app called "Copilot" on my PC yesterday and when I went to uninstall it I saw "Vivaldi" had been installed today. I know MS is force installing "Copilot" on some PCs but "Vivaldi" is not an MS app as far as I can tell so I don't know how it got on my machine ...

Any ideas as to how or why this might have happened?