we have encountered that JIRA headings in editor are not correct visualized. Perhaps it is mixed with other CSS of portal.
The headings h1. to h6. should have this style (like displayed under style in left up corner in editor of a task):
But the headings displayed are incorrect. It seems h1. and h2. are correct but then the style changes. Especially h4. is bigger than h3.:
Is this a bug in JIRA?