[glasser]

Our understanding of the current level of browser support is actually in a big comment at the beginning of every file aimed at the browser we generate that has a source map :)

    If you are using Chrome, open the Developer Tools and click the gear
    icon in its lower right corner. In the General Settings panel, turn
    on 'Enable source maps'.
    
    If you are using Firefox 23, go to `about:config` and set the
    `devtools.debugger.source-maps-enabled` preference to true.
    (The preference should be on by default in Firefox 24; versions
    older than 23 do not support source maps.)