So just discovered this tool called Lunacy from Icons8 that allow you to import, edit and export Sketch files.
Personally I use bubble as both my UI design and development tool.
For small projects i dont see the need to spend time designing prototypes in a Sketch and later having to redo everything in bubble when i can easily do everything in bubble.
But as a Windows user there are many times when i’m looking for design inspirations online I end up with sketch files online which I’m not able to view.
Looks like this tool is currently one of the best options if not the best for viewing, even editing sketch files on windows.