Hello Depending on the indentation amount on the line following a list item, when (org-insert-item) is evaluated.
Causes Emacs to soft freeze (can be canceled by pressing: C-g) or an error message is shown: (args-out-of-range 0 1) Reproduction Steps: Copy the following lines: 1. a b 2. c (the second line is indented by 3 spaces) Open a new buffer: C-x b test.org RET Switch to org mode: M-x org-mode RET Paste the copied lines: C-y Move the cursor to the end of the first line, after the: a (if the cursor is before the a, then the list item is added on a new line above probably as expected) Evaluate the following command: S-M-; (org-insert-item) RET Observed: The only visible change is that the cursor moves to the beginning of the "Eval:" prompt in the minibuffer. The Emacs cpu usage spikes (an infinite loop?) The soft freeze can be canceled by pressing: C-g The buffer now shows: 1. a 1. b 2. c The initial example above had three spaces before the: b The same soft freeze is observed if more spaces are added before the: b (I only tested it, up to five spaces, but I there might not be an upper limit) Indented by one or two spaces: If the initial second line is indented with one or two spaces, then Emacs shows an error message instead of freezing. A Backtrace buffer opens with the message: Debugger entered--Lisp error: (args-out-of-range 0 1) replace-match("1. " nil nil nil 1) #f(compiled-function (struct old-struct item) #<bytecode 0x497071>)(((1 0 "1. " nil nil nil 6) (6 0 "2. " nil nil nil 13) (16 0 "1. " nil nil nil 20)) ((1 0 "1. " nil nil nil 6) (6 0 "1. " nil nil nil 13) (16 0 "2. " nil nil nil 20)) 16) org-list-struct-apply-struct(((1 0 "1. " nil nil nil 6) (6 0 "2. " nil nil nil 13) (16 0 "1. " nil nil nil 20)) ((1 0 "1. " nil nil nil 6) (6 0 "1. " nil nil nil 13) (16 0 "2. " nil nil nil 20))) org-list-write-struct(((1 0 "1. " nil nil nil 6) (6 0 "2. " nil nil nil 13) (16 0 "1. " nil nil nil 20)) ((1) (6) (16))) org-insert-item() eval((org-insert-item) nil) eval-expression((org-insert-item) nil nil 127) funcall-interactively(eval-expression (org-insert-item) nil nil 127) call-interactively(eval-expression nil nil) command-execute(eval-expression) No indentation: If the indentation is removed from the second line: 1. a b 2. c Then it might be working as expected: 1. a 2. b 2. c a correctly numbered list item is inserted. The fourth lines list number: 2. c didn't change, but it might be expected since there was no indentation before the: b therefore it might be assumed that the list ended there. At least Emacs didn't freeze or show any errors. System info: Org mode version 9.3.7 (9.3.7-4-gba6ca7-elpaplus @ c:/Users/username/.emacs.d/elpa/org-plus-contrib-20200622/) GNU Emacs 26.3 (build 1, x86_64-w64-mingw32) of 2019-08-29 Windows 1903