debug output from firefox extension

Start firefox with -console flag

Call dumpln function from your code (copy of code from venkman)

var dumpln;

if (typeof document == "undefined") /* in xpcshell */
{
    dumpln = print;
}
else
{
    if (typeof dump == "function") {
        dumpln = function (str) {dump (str + "\n");}
    } else if (jsenv.HAS_RHINO) {
        dumpln = function (str) {
                     var out = java.lang.System.out;
                     out.println(str); out.flush();
                 }
    }
    else {
        dumpln = function () {} /* no suitable function */
    }
}