Load external HTML file with HMTL Snippet

Hi, for my use case it's necessary to load an external html file. This includes some document internal links to a header with a unique id. Like this example: Header with id:

Test header

Link: Go to test header Every time when I am click on the link, it will not jump to header and reloads the page. I am using the HTMLSnippet module v.3.9.8. Has someone an idea to solve this issue? Thanks and regards Ingo