Just updated from Ubuntu 20 to 24. Seems Thunderbird has not been auto-updating. I have three email accounts, each with multiple folders and sub-folders. I have three windows open, one for each account because they are for three purposes. Before the change each full height window could accommodate all the folders for its account (plus the un-expanded two lines for the other accounts). Now the folder lines are further apart and they don't fit so I can't tell when a new message arrives in one of the other accounts. Is there a setting for the spacing of the folder listing, and if so, what is it? Similarly I can not see so many messages listed in the classic layout without enlarging that pane and reducing the space for the messages. The spacing is larger than it used to be. Does it have a setting?

Thanks, David