Issue Summary

While it is possible to make any word in a page a heading, if you have the word main to be used as a heading, upon publishing a page, it creates a blank space between the text that was under the heading "main".

Steps to Reproduce

1. Create a new page
2. Type the word main (it must be a lowercase)
3. Highlight it to apply a heading to the word (any heading size)
4. Enter a new line and put some normal text
5. Publish the page

Expected Results

The text is under the heading, without any changes from the edit mode to the published view

Actual Results

If it is a lowercase main word, it creates a blank space between the heading and the text (or macro/quote).
If the word main used as a heading is not only lowercase letters, the issue does not happens.

Workaround

The issue does not occur if it is used Main as a heading (with the initial letter as Uppercase ) instead of main (all lowercase letters).