Question about the three panes view

Hello, from Portugal!

I am still new using DEVONthink Personal, started just two weeks ago. So I am not sure if my first post here is a feature request or if I am asking for a tip and trick help. Question is:
In the three panes view, I use to request all the vertical space for the right-down pane, when I am reading a pdf or typing a long text. I use to click twice on the horizontal separator and it goes up automatically. But later, to make it drop again, I have to search for the correct line and drop it down manually.
I see myself doing this quite often. I already searching for a menu option or keyboard command to do this, but didn’t found it.
Could there be an icon in the horizontal separator to move the separator to the top and later make it go down again, to half vertical position or something? Or a menu item or keyboard command? Or is it there and I didn’t found it yet?
Thanks for any answer.

(using DEVONthink Personal, version 2.0pb3 on a Mac intel core duo, OS 10.5.6)

This is a known glitch and will be improved by one of the next releases. But faster than collapsing/expanding the upper right pane or moving the separator might be to open the document in its own window via Cmd-O (and Cmd-W to close it again).

Yes, that is the way to go. Thanks.