@JJ-Pattaya

I support the both suggestions but

Seems more like a bug or design flaw. I suggested exactly the same (if in short it works in Edge this way) since the time the vertical tabs feature was first implented in Developer. I'm glad that I'm not alone with such thoughts regarding the design.
The other thing I don't like is that the sidebar and vertical pane are glued together now (autohide automatically means for the both panes).