Merge from origin/emacs-27

Merge from origin/emacs-27

8e8b46ef81 (origin/emacs-27) More accurate documentation of the "r" i...
dcb2015a5b Mention the GNU Kind Communications Guidelines in the FAQ
9882e63eea ; * CONTRIBUTE: Another wording change regarding tiny chan...
850f18ef23 Allow newlines in password prompts again in comint
c977370dd7 Avoid point movement when visiting image files
da64a257a4 ; * CONTRIBUTE: Yet another clarification of significant c...
d03f2a6ee9 Avoid assertion violation in callproc.c
dcc00bbb19 ; * CONTRIBUTE: Clarify the "15-lines" rule a bit more.