.XBF File Extension
File TypeXAML Binary File
What is an XBF file?
By producing the XBF file, loading and parsing performance becomes better, especially when loading XAML files that define large resources.
The XBF file will appear as App.xbf in the subdirectory of its related application.
NOTE: If you compile your XAML file into the XBF format you should still maintain the XAML in its text state so that it remains human-readable.
App.xbf - Default name given to the binary representation of the XAML file of each app.