This is an incomplete initial bug report. I don't have time right now to chase down all the details. A couple of times in the past month, the subheadings in the org file I'm working on (with lots of org-babel code blocks) disappear. does not fold or unfold those headings, although the indicator (...) still shows. In desperation, I switch to fundamental-mode, but the text is still not in the buffer. I save the buffer under a different filename to find that all the missing text is in the file. Has anyone else seen this? summary: 1. subheading text disappears from org file, even in fundamental 2. saving the buffer shows that the disappearance is cosmetic only 3. I have not established reproducible conditions for this yet. Emacs : GNU Emacs 29.1 (build 2, x86_64-apple-darwin22.5.0, GTK+ Version 3.24.38, cairo version 1.17.6) of 2023-08-07 Package: Org mode version 9.6.6 (release_9.6.6 @ /opt/local/share/emacs/29.1/lisp/org/) current state: ============== (setq org-noter--doc-goto-location-hook '(org-noter-pdf--goto-location) org-link-elisp-confirm-function 'yes-or-no-p org-ditaa-jar-path "/opt/local/share/java/ditaa-0.11.0-standalone.jar" org-noter-supported-modes '(doc-view-mode pdf-view-mode nov-mode) org-bibtex-headline-format-function #[257 "\300 \236A\207" [:title] 3 "\n\n(fn ENTRY)"] org-download-file-format-function 'org-download-file-format-default org-agenda-files '("~/Syncbox/files/gtd.org") org-persist-after-read-hook '(org-element--cache-persist-after-read) org-export-before-parsing-hook '(org-attach-expand-links) org-noter-arrow-horizontal-offset -30 org-cycle-tab-first-hook '(org-babel-hide-result-toggle-maybe org-babel-header-arg-expand) org-noter-doc-split-fraction '(0.67 . 0.9) org-default-notes-file "~/Syncbox/files/.notes" org-archive-hook '(org-attach-archive-delete-maybe) org-file-apps '((auto-mode . emacs) ("\\.x?html?\\'" . default) ("\\.pdf\\'" . default) ("\\.jpe?g\\'" . "gqview -t %s &")) org-noter--pretty-print-location-for-title-hook '(org-noter-pdf--pretty-print-location-for-title) org-odt-format-inlinetask-function 'org-odt-format-inlinetask-default-function org-ascii-format-drawer-function #[771 " \207" [] 4 "\n\n(fn NAME CONTENTS WIDTH)"] org-cycle-hook '(org-cycle-hide-archived-subtrees org-cycle-show-empty-lines org-cycle-optimize-window-after-visibility-change org-cycle-display-inline-images) org-noter-auto-save-last-location t org-persist-before-read-hook '(org-element--cache-persist-before-read) org-noter--pretty-print-highlight-location-hook '(org-noter-pdf--pretty-print-highlight) org-mode-hook '(#[0 "\301\211 \207" [imenu-create-index-function org-imenu-get-tree] 2] er/add-org-mode-expansions org-appear-mode #[0 "\300\301\302\303\304$\207" [add-hook change-major-mode-hook org-fold-show-all append local] 5] #[0 "\300\301\302\303\304$\207" [add-hook change-major-mode-hook org-babel-show-result-all append local] 5] org-babel-result-hide-spec org-babel-hide-all-hashes) org-babel-load-languages '((emacs-lisp . t) (ditaa . t) (perl . t) (python . t) (octave . t) (shell . t) (matlab . t)) org-appear-autoentities t org-noter--pretty-print-location-hook '(org-noter-pdf--pretty-print-location) org-latex-format-drawer-function #[514 "\207" [] 3 "\n\n(fn _ CONTENTS)"] org-ellipsis " ↧" org-download-abbreviate-filename-function 'file-relative-name org-latex-format-headline-function 'org-latex-format-headline-default-function org-confirm-shell-link-function 'yes-or-no-p org-download-annotate-function 'org-download-annotate-default org-appear-autosubmarkers t org-adapt-indentation t org-html-format-drawer-function #[514 "\207" [] 3 "\n\n(fn NAME CONTENTS)"] org-download-screenshot-method "screencapture -i %s" outline-isearch-open-invisible-function 'outline-isearch-open-invisible org-odt-format-headline-function 'org-odt-format-headline-default-function org-appear-inside-latex t org-agenda-before-write-hook '(org-agenda-add-entry-text) org-babel-tangle-lang-exts '(("python" . "py") ("perl" . "pl") ("emacs-lisp" . "el") ("elisp" . "el")) org-src-mode-hook '(org-src-babel-configure-edit-buffer org-src-mode-configure-edit-buffer) org-confirm-elisp-link-function 'yes-or-no-p org-ditaa-eps-jar-path "/opt/local/share/emacs/29.1/lisp/contrib/scripts/DitaaEps.jar" org-id-link-to-org-use-id t org-noter-headline-title-decoration "/" org-appear-autoemphasis nil org-noter--show-arrow-hook '(org-noter-pdf--show-arrow) org-speed-command-hook '(org-speed-command-activate org-babel-speed-command-activate) org-html-format-inlinetask-function 'org-html-format-inlinetask-default-function org-ascii-format-inlinetask-function 'org-ascii-format-inlinetask-default org-noter-arrow-background-color "cyan" org-odt-format-drawer-function #[514 "\207" [] 3 "\n\n(fn NAME CONTENTS)"] org-noter--add-highlight-hook '(org-noter-pdf--highlight-location) org-noter--get-current-view-hook '(org-noter-pdf--get-current-view) org-noter-arrow-foreground-color "black" org-noter-set-up-document-hook '(org-noter-pdf--doc-view-setup-handler org-noter-pdf--pdf-view-setup-handler) org-noter--get-containing-element-hook '(org-noter--get-containing-heading org-noter--get-containing-property-drawer) org-fold-core-isearch-open-function 'org-fold--isearch-reveal org-latex-format-inlinetask-function 'org-latex-format-inlinetask-default-function org-noter--convert-to-location-cons-hook '(org-noter-pdf--convert-to-location-cons) org-persist-before-write-hook '(org-element--cache-persist-before-write) org-tab-first-hook '(org-babel-hide-result-toggle-maybe org-babel-header-arg-expand) org-link-shell-confirm-function 'yes-or-no-p org-babel-pre-tangle-hook '(save-buffer) org-agenda-loop-over-headlines-in-active-region nil org-noter--get-precise-info-hook '(org-noter-pdf--doc-view-get-precise-info org-noter-pdf--pdf-view-get-precise-info) org-noter--get-highlight-location-hook '(org-noter-pdf--get-highlight) org-occur-hook '(org-first-headline-recenter) org-metadown-hook '(org-babel-pop-to-session-maybe) org-noter--doc-approx-location-hook '(org-noter-pdf--approx-location-cons) org-link-parameters '(("eww" :follow org-eww-open :store org-eww-store-link) ("rmail" :follow org-rmail-open :store org-rmail-store-link) ("mhe" :follow org-mhe-open :store org-mhe-store-link) ("irc" :follow org-irc-visit :store org-irc-store-link :export org-irc-export) ("info" :follow org-info-open :export org-info-export :store org-info-store-link :insert-description org-info-description-as-command) ("gnus" :follow org-gnus-open :store org-gnus-store-link) ("docview" :follow org-docview-open :export org-docview-export :store org-docview-store-link) ("bibtex" :follow org-bibtex-open :store org-bibtex-store-link) ("bbdb" :follow org-bbdb-open :export org-bbdb-export :complete org-bbdb-complete-link :store org-bbdb-store-link) ("w3m" :store org-w3m-store-link) ("doi" :follow org-link-doi-open :export org-link-doi-export) ("attachment" :follow org-attach-follow :complete org-attach-complete-link) ("id" :follow org-id-open) ("file+sys") ("file+emacs") ("shell" :follow org-link--open-shell) ("news" :follow #[514 "\301\300\302 Q \"\207" ["news" browse-url ":"] 6 "\n\n(fn URL ARG)"]) ("mailto" :follow #[514 "\301\300\302 Q \"\207" ["mailto" browse-url ":"] 6 "\n\n(fn URL ARG)"]) ("https" :follow #[514 "\301\300\302 Q \"\207" ["https" browse-url ":"] 6 "\n\n(fn URL ARG)"]) ("http" :follow #[514 "\301\300\302 Q \"\207" ["http" browse-url ":"] 6 "\n\n(fn URL ARG)"]) ("ftp" :follow #[514 "\301\300\302 Q \"\207" ["ftp" browse-url ":"] 6 "\n\n(fn URL ARG)"]) ("help" :follow org-link--open-help :store org-link--store-help) ("file" :complete org-link-complete-file) ("elisp" :follow org-link--open-elisp)) org-noter-get-buffer-file-name-hook '(org-noter-pdf--get-buffer-file-name) org-html-format-headline-function 'org-html-format-headline-default-function org-metaup-hook '(org-babel-load-in-session-maybe) org-noter-get-selected-text-hook '(org-noter-pdf--get-selected-text) org-noter-create-session-from-document-hook '(org-noter--create-session-from-document-file-default) org-startup-with-inline-images t org-download-link-format-function 'org-download-link-format-function-default org-return-follows-link t org-id-method 'ts org-download-image-dir ".figs" org-noter-create-skeleton-functions '(org-noter-pdf--create-skeleton) org-list-allow-alphabetical t org-noter-save-notes-at-end-of-session t )