I was recently trying to make the hide details feature bold and I came up with this bug. Once I use <b> to make it bold and afterwards </b> inside the bracket, the title name changes. That’s a weird behavior and the best way to describe it is by reproducing it below:
Just found another issue. Once you align it in the center and then you use to align it back inside the bracket, the text below that command gets placed outside the details feature:
<div align=center>
[details="Hello!"]
I am in the center
</div>
Hello!
[/details]