Broken UI for rich text editor

We are using the editor core component of latest jira design for our add on and we are also supporting wikimarkup as per old jira.
we have identified one use case where our client is facing an issue in that component and we have found that it exists in jira also.
When we add a table in description field in new issue view and add a header and just put a new line after that and view that issue in old view the UI gets broken. (refer screenshot).

We also face a similar issue in the component we used. Please let us know a way on how to fix this issue