Why is this browser so bugged. Help needed.

[mixElll]

@Pathduck I only need passwords. History is optional.

[Pathduck]

@mixElll You don't copy files from the profile.

https://help.vivaldi.com/desktop/tools/import-and-export-browser-data/

You export Bookmarks as a HTML file for import.
You export Passwords as a CSV file for import.

You might try copying your History file from your Opera profile into your Vivaldi profile but this is not supported and might not work at all or crash stuff.

Extensions that have been installed from the Opera Store will probably not work in any case.