Peter Mao <peter.mao@gmail.com> writes:

> 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.  <TAB> does not
> fold or unfold those headings, although the indicator (...) still shows.
> ...
> 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.

Might be yet another problem with isearch + folding via text properties.
You may try to set `org-fold-core-style' to 'overlays.

--
Ihor Radchenko // yantar92,
Org mode contributor,
Learn more about Org mode at <https://orgmode.org/>.
Support Org development at <https://liberapay.com/org-mode>,
or support my work at <https://liberapay.com/yantar92>