

3.1.2: possible Cygwin DLL console or pty bug when forwarding the stdout to less within the Windows-Console (cmd.exe Win10 build 1809, 1903, 1909)

Since 3.1.1 (including current 3.1.3-snapshot) I have the problem 
that escape sequences (single character, not the three letters "ESC", plus "[...m") suddenly appear inside less, 
and when I leave less, the cmd.exe console displays escape sequences at the cursor up (down, left, right) and does not respond correctly to cls.
It seems that less initializes the console and while less prints something, another program deinitializes the console.
With 3.0.7 cygwin1.dll it works fine. (But I want xterm256-color from 3.1.x cygwin1.dll.)

Here simple examples:

1)
C:\Users\slasch>ls C:\Windows | less -E +G

C:\Users\slasch>^[[A


2)
C:\Users\slasch>ls C:\cygwin64\bin | less  # then press G and q
...
-rwxr-xr-x 1 slasch slasch    1940 Aug 26  2016 zcat
-rwxr-xr-x 1 slasch slasch    1665 Aug 26  2016 zcmp
-rwxr-xr-x 1 slasch slasch    5667 Aug 26  2016 zdiff
-rwxr-xr-x 1 slasch slasch      29 Aug 26  2016 zegrep
-rwxr-xr-x 1 slasch slasch      29 Aug 26  2016 zfgrep
-rwxr-xr-x 1 slasch slasch    2038 Aug 26  2016 zforce
-rwxr-xr-x 1 slasch slasch    7444 Aug 26  2016 zgrep
-rwxr-xr-x 1 slasch slasch    2154 Aug 26  2016 zless
-rwxr-xr-x 1 slasch slasch    1816 Aug 26  2016 zmore
-rwxr-xr-x 1 slasch slasch    4392 Aug 26  2016 znew
[K[?1l>[?1049l[23;0;0t7[3g[1;9HH[1;17HH[1;25HH[1;33HH[1;41HH[1;49HH[1;57HH[1;65HH[1;73HH[1;81HH[1;89HH[1;97HH[1;105HH[1;113HH8
C:\Users\slasch>^[OA^[OA


3) # other PC other commands (Strawberry-Perl with "cmd.exe dir" stdout forwarded to less) to show the single "escape character"
total 320[m                                                                             
drwxr-xr-x+ 1 foo    foo                 0 Feb 13 17:40 .[m                           
drwxr-xr-x+ 1 foo    foo                 0 Feb 13 17:42 ..[m                          
-rwxr-xr-x  1 sadmin Administratoren 35147 Apr 30  2019 COPYING[m                     
-rwxr-xr-x  1 sadmin Administratoren  1458 Apr 30  2019 CYGWIN_LICENSE[m              
-rw-r--r--  1 foo    foo              2045 Dec 16  2017 _autorebase.README[m          
-rw-r--r--  1 foo    foo              2653 Apr  5  2013 alternatives.README[m         
-rw-r--r--  1 foo    foo              1694 Jul  9  2013 autoconf.README[m             
-rw-r--r--  1 foo    foo              2096 Jul  9  2013 autoconf2.1.README[m          
-rw-r--r--  1 foo    foo              1806 Jul 29  2013 automake1.9.README[m          
-rw-r--r--  1 foo    foo              4227 Apr  1  2019 autossh.README[m              
-rw-r--r--  1 foo    foo             17474 Jan 27  2017 bash.README[m                 
-rw-r--r--  1 sadmin Administratoren  1468 Aug  9  2010 build-docbook-catalog.README[m
-rw-r--r--  1 foo    foo             13113 Feb  3  2017 coreutils.README[m            
-rw-rw----  1 foo    foo              1863 Apr 16  2013 ctags-5.8.README[m            
-rw-r--r--  1 foo    foo             20685 Jan 28  2015 cygrunsrv.README[m            
-rw-r--r--  1 sadmin Administratoren  8136 Apr 30  2019 cygserver.README[m            
-rw-r--r--  1 foo    foo              2303 Feb 17  2017 dash.README[m                 
-rw-r--r--  1 foo    foo              3671 Mar 10  2016 diffstat.README[m             
-rw-r--r--  1 foo    foo              2749 Dec  7  2016 diffutils.README[m            
-rw-r--r--  1 foo    foo              1965 Oct  3 19:59 dos2unix.README[m             
-rw-r--r--  1 foo    foo               626 Oct 31  2014 editrights.README[m           
-rw-r--r--  1 foo    foo              4829 Mar 11  2016 findutils.README[m            
-rwxr-xr-x  1 foo    foo                 0 Dec 13 09:28 gawk[m                        
:[K