firefox --class WM_CLASS_user_defined_value (firefox3)

[reikred at gmail.com]

It used to be (in any firefox 2.0.0.X and below) that one could
force the value of the xprop WM_CLASS value to some user-defined
value rather than a default value, by using a command line argument.

For example
#version 2.0.0.16 started with --class=Firefox2
% xprop | grep WM_CLASS
WM_CLASS(STRING) = "gecko", "Firefox2"

This is useful for window managers that use WM_CLASS to sort icons.

Questions:

1. What happened in the source code, and where?
2. is there a workaround that I can use?

I have grep'ed the source code for 2.0.0.16 and 3.01 without
coming to any conclusions.