select_pane not working correctly with multiple sessions

The code of select_pane is:

        if target_pane in ["-l", "-U", "-D", "-L", "-R"]:
            proc = self.cmd("select-pane", "-t%s" % self.window_id, target_pane)
        else:
            proc = self.cmd("select-pane", "-t%s" % target_pane)

If calling it with a pane index (e.g. window.select_pane(3)) the resulting command will be select-pane -t3. This will result in self.server.cmd('select-pane -t3').

=> It will always change the pane in the session number 1.

Shouldn't there be some kind of further target description like
select-pane -t $3:@9.3 (change to pane 3 in session 3, window9)
?

Start at the select_pane implementation shown in the issue and trace how self.cmd passes its target to self.server.cmd. Reproduce window.select_pane(3) with multiple sessions, then verify that the generated target retains the session and window context and selects pane 3 in the requested session.