Version 4.0, I found the option(Trim tailing spaces and Save) from Key-binding options window. It is more convinient than executing 'trim' command each time. However, it will intert extra 8 spaces at the cursor unless the cursor is at the end-of-line. Is it a bug?

And about the line comment (Ctrl-Q). Could it comment the current line when there is no text selected? It is sugar for commenting single line.