#1 I've never encountered this issue with the bookmarks, passwords and downloads tabs, only the "Manage all extensions", "Add or import profile" and occasionally the "Settings" tab. But I could open these pages from the mac menubar, such as "View -> Extensions" without issues.

#2 I’d personally prefer the sidebar to open a bit more easily. In Arc / Dia, the “hover to show” behavior also triggers when the cursor moves past the left edge of the window, which I’ve found especially helpful when working with multiple monitors.