WMR allows bringing Windows Desktop to VR. However you will face issues when moving mouse focus from VR cockpit to the displayed desktop.
Other options:
FSDesktop (limited mouse support)
All In One Tablet by Flightsimulator.me
- simplified browser or
- controlling the desktop of remote PC with VNC.
Why do you need browser while flying? There are various panels showing maps, VATSIM data etc. in the VR cockpit.