Steps to replicate the issue (include links if applicable):

• Ensure that parsoid is turned on
• Go to https://en.m.wikipedia.org/wiki/Yugoslav_monitor_Sava
• Observe that sections are neither editable nor collapsible
• Inspect section heading

What happens?:

h2 is not wrapped in a div

What should have happened instead?:

h2 should be wrapped in a div with mw-heading and mw-heading2 classes

Other information (browser name/version, screenshots, etc.):

https://wikimedia.slack.com/archives/C024Z8K9CAU/p1722291285617749
@cscott had some theories about why this is happening related to the section editing link transform