There's something weird with headings that can cause unfolding to fail. Headings can
be folded with TAB refuse to unfold - they need Shift-TAB to see the contents. This
is scary as it looks like content has been accidentally deleted whereas it's really
just hidden.
The TAB-cycling worked as expected in Org 9.1.9 for the following example but fails
in 9.4.
The example below illustrates the difficulties:
* Block 1 - you can delete X to leave two empty lines and TAB on "Block 1" (or
1a)
cycles as expected - GOOD!
But if the last line isn't empty but has spaces:
* Block 2 - deleting X (leaving empty line) and then Z to leave the last line
with
just a space (one or more) and heading will fold on TAB /but won't unfold/.
Shift-Tab is needed.
* Block 3 - the same symptoms as Block 2 but has a subtree to show
"Folded/Children/Subtree" when Tab-cycling on level one heading.
Cheers
Giovanni
===================
* Block 1 - OK
Block 1 text
** Block 1a heading
Block 1a content
X
X
* BAD BLOCK 2 - Delete X & Z, then TAB WON'T UNFOLD
Block 2 content
X
Z
* BAD BLOCK 3 - TAB WON'T UNFOLD
Block 2 content
** BAD BLOCK 3a
Block 3a content
X
Z
* Block 4 - OK
The end