Thanks. I’m glad that you liked it!
A) I am already working on it. needs some extra work to implement it but i’ll get it done.
B) I intentionally kept it this way because:
a.) resizing 2 documents (when closing/opening pane) would affect the user experience.
b.) right pane is secondary document primarily opened to refer something. So more width should be given to the primary document (left pane) where the user would work upon.
However, these are just my personal opinions which could be different from others. I could add a settings which would toggle “Auto-adjust” doc pane width.