bug#38013: [PATCH] Rectangular region selection with mouse

[Eli Zaretskii]

> From: Mattias Engdegård <mattiase@acm.org>
> Date: Sat, 9 Nov 2019 20:32:46 +0100
> Cc: rudalics@gmx.at, 38013@debbugs.gnu.org
> 
> In the first patch, the start and end corners of the rectangle had to be a 
> point in the buffer; ie, not a position beyond the end of a line or in the 
> middle of a tab character. That was not only unnecessarily restrictive but 
> also made the rectangle flutter back and forth as the dragged corner passed 
> through lines of different length. Now the rectangle corners can be any 
> character cell.

OK, that's good.

> If that was not the reason for your concern, would you mind describing the 
> problem more in detail and how to reproduce it? 

I still see a 1-pixel thin "region" sometimes, which causes the text
to move horizontally.  More importantly, if I drag the mouse through a
TAB, it moves in jumps of several columns, not one column at a time.