* lisp/repeat.el (repeat-keep-prefix): New defcustom.

* lisp/repeat.el (repeat-keep-prefix): New defcustom.

* lisp/repeat.el (repeat-map): New autoloaded global variable.
(repeat-post-hook): Use 'repeat-map' when non-nil
and reset it to nil afterwards.
(repeat-post-hook): Keep the current prefix when
'repeat-keep-prefix' is non-nil.

* lisp/window.el (other-window-repeat-map): Add "O" that sets
'repeat-map' to 'other-window-repeat-map' before calling
'(other-window -1)'.

https://lists.gnu.org/archive/html/emacs-devel/2021-03/msg01387.html