%artist%- %title%

Artist1- Song1

%artist% - %title%

Artist1 - Song1

I guess it's a typo? But then again it's quite widespread if it's indeed a typo, because not only %artist%- %title% but also the other suggestions such as %title%- %artist% & %track%- ℅title℅. I'm on Fedora Silverblue, latest version of Tagger (flatpak) btw.