on Thunderbird window resize: increasing window height allocates all the additional height to the index vs message pane

Does anyone else increase the size of the Thunderbird window hoping to see more of the email in the message pane? But instead, we just get a longer index of messages. Then have to move the border of the message pane up. This is only for the occasional need to see more in a single page, but frequent enough that I'm repeatedly having to resize the pane for individual message, then resize it again when I return to my normal window height. Yeah, I know I can open in separate tab, but seems allocating the space to index/message pane on window resize, ought to at least be done equally, if not all to the message pane.