in maint. for a very long time, i have done (setq org-element-use-cache nil) because i kept getting errors or buffer corruption.
now, errors occur even with that setting. all i did was press return. this followed trying to comment a blank line (which i wish emacs would just do). i cannot do a thorough bug report or q/a at this time but thought this might be useful. Debugger entered--Lisp error: (error "Stack overflow in regexp matcher") re-search-forward("^\\(?:\\*+ \\|\\[\\(?:[0-9]+\\|fn:[-_[:word:]]+\\)\\]\\|%%(\\|[ ]*\\(?:$\\||\\|\\+\\(?:-+\\+\\)+[ ]*$\\|#\\(?: \\|$\\|\\+\\(?:BEGIN_\\S-+\\|\\S-+\\(?:\\[.*\\]\\)?:[ ]*\\)\\)\\|:\\(?: \\|$\\|[-_[:word:]]+:[ ]*$\\)\\|-\\{5,\\}[ ]*$\\|\\\\begin{\\([A-Za-z0-9*]+\\)}\\|CLOCK:\\|\\(?:[-+*]\\|\\(?:[0-9]+\\)[.)]\\)\\(?:[ ]\\|$\\)\\)\\)" 422741 move) org-element-paragraph-parser(422741 (211182)) org-element--current-element(422741 element nil nil) byte-code... org-element--parse-to(211350) org-element-at-point() byte-code... org-element-context() org-return() call-interactively(org-return nil nil) command-execute(org-return) -- The Kafka Pandemic: http://thekafkapandemic.blogspot.com The disease DOES progress. MANY people have died from it. And ANYBODY can get it. Denmark: free Karina Hansen NOW.