I open and close the project bar frequently and tabbed windows have an issue with the document width. If you close the project bar, switch to another tab, open a project bar, switch to a tab, open a project bar, the window width expands every time. It can get itself into a state with really wide windows or alternately really narrow windows. Some kind of calculation thing, I’m not sure what sort of logic is intended, but at the moment it seems inconsistent with the width calculations.
Taskpaper 3.6, macOS Sierra 10.12.2