[openbox] openbox Digest, Vol 111, Issue 9

[Jim Rees]

Gary wrote:

  All of the _OB_APP_ items for a Firefox window are the same for all
  Firefox windows, making it impossible to have Openbox configure each
  Firefox window uniquely. However, _NET_WM_VISIBLE_NAME is unique for
  each Firefox window that is opening a specific webpage, in that it
  displays the text from the window's title bar.

That's one of the more annoying misfeatures of Firefox. There are various
add-ons that claim to fix this, but I haven't tried them. You could try
"Custom Titlebar Text".