When Joomla added module to articles feature, firstly was code
{loadmodule mod_custom,[module title]}
Later was changed to
{loadmoduleid [ID}}
Long time ago, I discovered problem with module displays. When old code a module, exists few times ia duplicated. This bug exists only for J4,not for J5

Steps to reproduce the issue

1. Create new custom module and add small image for example. Set "Github" for title.
   
2. To new article, paste this code

Text 1

{loadmodule mod_custom,Github}

Text 2

{loadmodule mod_custom,Github}

Text 3

{loadmodule mod_custom,Github}

Expected result

Actual result

Double view of module for default template:

System information (as much as possible)

10.6.15-MariaDB-cll-lve
PHP Version 8.1.26
Web Server | LiteSpeed

Joomla! Version | Joomla! 4.4.1 Stable [ Pamoja ] 28-November-2023 16:00 GMT

Additional comments