Nested collapsible elements incorrectly interact with each other

Inserting an expand macro inside another expand macro is working well.
However inserting a collapsible code macro inside an expand macro, does not.

Step to reproduce:

• create a page
• insert an expand macro with a dummy text
• add into this expand macro, a code macro with a dummy text and chek "collapsible" option
• save the page

Then:

• expand the text
• expand the code block

The expand macro then collapses and you have to expand it again to read the content of the code block.

Here is an example page in Confluence storage format:

<ac:structured-macro ac:name="expand"><ac:rich-text-body>
<p>Expand level 1</p><ac:structured-macro ac:name="expand"><ac:rich-text-body>Expand level 2</ac:rich-text-body></ac:structured-macro><ac:structured-macro ac:name="code"><ac:parameter ac:name="language">bash</ac:parameter><ac:parameter ac:name="collapse">true</ac:parameter><ac:plain-text-body><![CDATA[Code expand]]></ac:plain-text-body></ac:structured-macro></ac:rich-text-body></ac:structured-macro>