TheWay support in DCS Web Viewer.
You can now convert flight plans / waypoints from any mission as TheWay .tw file. Open a .miz file, click a waypoint or unit popup and click "Export TheWay" to save.
Or "Edit TheWay" to open a JSON editor, make your desired changes, then save as .json and rename to .tw.
You can also convert drawn polylines via the measure tool, in the main menu.
https://dcs-web-editor.github.io/dcs-web-viewer-deploy/
live map
https://dcs-web-editor.github.io/dcs-web-viewer-deploy/live