Bing StreetSide is alternative to Google Street View which can be used for OpenStreetMap mapping. There is a MicrosoftStreetside plugin for JOSM but it doesn’t work for me due to dependencies of JavaFX/360 views.

I have managed to use it via Utilsplugin2.

1. Edit => Preferences (F12) => Utilsplugin2 settings
2. Add new row with name Bing StreetSide and url https://www.bing.com/maps?cp={#lat}%7E{#lon}&lvl=19.0&style=x.
   In the case of issues one can edit customurl.txt. For Linux/Flatpak it’s located at ~/.var/app/org.openstreetmap.josm/data/JOSM/plugins/utilsplugin2/customurl.txt.
3. Choose Bing StreetSide in Data => Select custom URL
4. Now you can see Bing StreetSide via Data => Open custom URL (Shift+H)

If StreetSide is available at given location it will be displayed. Otherwise map is shown with streets colored blue where it’s available.