When I try to toggle the open/closed status of a folder in the left sidebar (in the webapp), the +/- button disappears and nothing happens when I click that area. If I position my pointer right *next* to the +/- button, I can open and close the folder. That’s fussy and annoying.
Once in a while the +/- button *doesn’t* disappear, and then it works like I’d suspect, but the majority of the time I’ve used it, hovering over the button makes it go away.