Excel Online should be able to open a XLST file properly
If I have a stored template file in OneDrive Excel Online should be able to handle it properly, i.e., it should open a file based on the template and prompt to name it. Then it should behave as normal. Not having this function seems bizarre.
I want to store a couple of template files in OneDrive so I can always get at them and use them from wherever I am working. Easy.