Is there a way to see generated javascript all the time?
Of course there's a 'Preview compiled coffescript' command that will open modal window. not exactly the thing I'm looking for.
Also you always can split window vertically and have both .coffee and .js opened. But then, it won't change automatically when you navigate to a different coffeescript file.
And I'm hoping to have a side panel that maybe supports source maps too.
Possible?
No, but you can file a feature request here: http://youtrack.jetbrains.com/dashboard#newissue=yes
It might be useful for other languages too: TypeScript, Less, Sass, etc