Steps to reproduce the issue

• fresh install Joomla 3.8.12
• create new custom module with some content
• create new article
• put in some content and loadmodule of the cretaed custome module
• repeat within the same article / content plus loadmodule several times
  text
  {loadposition position-4}
  text
  {loadposition position-4}
  text
  {loadposition position-4}
  text
• connect menu-item with article
• check created HTML

Expected result

• on each position the module is loaded, there should be just one headline and one wrapping div-combination of div-class-custom and div-class-moduletable

Actual result

• on the first position where the module is loaded it's fine
• second, doubled up headline and wrapping div
• third, three headlines and three wrapping combinations of the both div
• and so on, increasing …

System information (as much as possible)

Joomla 3.8.12
PHP 7.2.3
Need more information?

Additional comments

It doesn't make a difference if loadposition or loadmodule is used, or if the module is on an defined or custom position.

I used this construct of calling more than one time the same module, to import an SVG mark up several times within the same article for design reasons. As the SVG will be adjusted in future, I just wanted to place it once in the module section.
Workaround for now … multiple modules with same content/ different calls within the article …

You guys are still doing a great job!
Many thanks for all that work you do!