Merge from origin/emacs-26

Merge from origin/emacs-26

d382d2bfc5 * etc/DEBUG (Getting control to the debugger): Fix grammar.
687af4c8e8 * lisp/vc/vc.el (vc-region-history): log-view-vc-fileset h...
43e2aafae3 Don't bind dframe events on load (Bug#29599)
ab31bf3c5f * lisp/textmodes/picture.el (picture-mode-exit): Doc fix. ...
ed44d92fa6 * lisp/textmodes/picture.el (picture-open-line): Doc fix. ...
b87a772612 Fix description of 'emacs-internal'
a5256da588 Update PROBLEMS with selection-related issues
c59ecb005e New customization variable for python-mode indentation (Bu...
4e20c8f220 Fix menu keyboard shortcuts on macOS (Bug#29595)

# Conflicts:
#	etc/NEWS