A FileTreeComponent has the ability to display native icons for files. Those are generated in the function Image juce_createIconForFile (const File&) which is part of JUCE’ private API. Is there any possibility to make this function part of the public API?
Preferably with arguments to specify the desired dimensions of the resulting Image. But it’d be already happy having at least access to the function as is.
It’s not implemented on all platforms, so probably not something we’d add to the public API at the moment. You don’t need to change anything in juce to be able to call it yourself though, you just declare the function prototype in your own code and then call it.
I had tried that originally but forgot that we are doing some namespace magic … I guess your reassurance helped me solve that knot 
I suppose for linux there is almost no solution that works reliably across distributions. Generic folder and file icon would be ok there …