It seems this is not really true/accurate. I decided to test this, by switching to “Single Panel”, and I can use hotkeys to snap the window to half the screen just as @Phylu stated.
I then switched back to “Two Panel” mode, and to my surprise (not really…), I’m able to snap the window to half the screen using hotkeys. Everything is working as it should, and whatever minimum width is ignored.
There shouldn’t be any limitations on minimum widths for a window. If the user wants to snap Mailspring to half its screen, the user should be allowed to do so. Also, it’s completely readable on a 1080p monitor, and from now on, my favorite way of using Mailspring
There’s still a bug, by not having a consistent behavior on window resizing. If Mailspring decides to enforce a minimum window width (which I implore, please don’t), there should be a warning/note on the settings windows with a description of this expected behavior. (i.e. Mailspring won’t be able to snap to half the screen when using two-panel mode). But please, allow us, users, to use Mailspring how we see fit.
FYI, restarting Mailspring brings back the bug, in other words, we can’t resize/snap the window to half the screen.