I don't like all my windows to constantly re-arrange and re-size every time I open or close a split. In particular, I don't want my "Terminal" windows to ever be zoomed up to 200 columns wide; in fact, I prefer them to stay at precisely 105 columns wide, and for all other windows to share any remaining space.
Is there a way for me to say "when automatically re-arranging window-panes, please keep this vertical-split at exactly 105 columns wide?"
(For reference, I'm talking about the behaviour of Vim's :set winfixwidth.)