@andro, It seems throwing an exception is the default behaviour of Embed FontAwesome plugin.
You can change its behaviour by setting its configuration options. According the docs:
fail_behaviour ( hard / soft ): Behaviour when icon files are missing ( hard => throw an exception, soft => replace the icon with a question mark).
I think I would prefer the plugin to throw an exception (‘hard’) and show me immediately and clearely which svg is missing. A kind of fail early approach. When using the ‘soft’ approach a missing svg is easily overlooked unless every web page is checked carefully.