Unlike older versions of Visio Viewer that required a local plugin, modern Visio viewing in Office 365 is completely cloud-based.
The Visio Viewer in Office 365 is fine for reading diagrams but useless for editing. For occasional changes, use Visio for the web ($5/user/month). For heavy use, get Visio Plan 2 . office 365 visio viewer
The Office 365 Visio Viewer! Here are some useful text and information about it: Unlike older versions of Visio Viewer that required