Jira Issue macro appends content from previous loaded/cached JIM when placed right below a heading

Issue Summary

The new Jira Issue macro may incorrectly append content belonging to a JIM previously loaded when you place them right underneath a Heading.

This seems to work differently depending on the content of the heading - it's more likely to happen for shorter texts and when there's an emoji, and less likely to happen when the heading is a longer text or has some spaces between the heading and the macro. 

Keep in mind that a minor adjustment to the page can make the bug to happen or not, so it may be tricky to reproduce it. See internal comments for additional info.

Steps to Reproduce

1. Create two pages (A & B) with only a heading and a Jira Issue macro right underneath.
2. Ensure the Jira Issue macros have distinct JQL queries
3. Ensure there's no text or space between the headings and the macro
4. Navigate repeatedly between the two pages

Expected Results

The Jira Issue macros on each page will always display the content their query was set to.

Actual Results

The Jira Issue macros append content from Page A JIM into Page B and Page B JIM into Page A.

Workaround

You can either refresh the page or the macro itself to see the correct list of results.

Alternatively, you can try to change the content of the page - include some text, or other elements, between the headings and the Jira Issue macros, or even change the Headings to something else and test if the incorrect behavior stops. This is intermittent and seems to change on every new version of the page.

Lastly, it's still possible to use the Legacy Jira macro.