.SUBLIME-MENU File

The sublime-menu file extension is exclusively related to a specific XLM format used by Sublime Text editor.

These files are used to define menu and menu elements used in the program. 

Files with .sublime-menu extension are menu settings for Sublime Text text editor.

How to open:

You can edit the file in the very same text editor for which this setting file is - Sublime Text.

How to convert:

Probably cannot be converted to anything else.