This seems to work
* A
* B
* B1
* B2
<details><summary>Summary</summary>This text will be hidden</details>
* B3
* C
Produces:
-
A
-
B
-
B1
-
B2
Summary
This text will be hidden -
B3
-
-
C
This seems to work
* A
* B
* B1
* B2
<details><summary>Summary</summary>This text will be hidden</details>
* B3
* C
Produces:
A
B
B1
B2
B3
C