How to programmatically create a slot and slot a HTMLElement into it?

How to programmatically create a slot and slot a HTMLElement into it? slot html The slot> and template> tags The template> tag holds HTML code that won't be rendered by browsers until it's properly added to the document, slot btn How should I decide to use one method over the other? It seems like if I want to be able to specify HTML rather than just text, I would choose

slot btn A slot is a function that is called in response to a particular signal Qt's widgets have many pre-defined slots, but it is common practice to subclass widgets

slot strategy The HTML slot> element allows users to create shadow DOM The shadow tree is a collection of elements in a On this Page The HTML slot> element—part of the Web Components technology suite—is a placeholder inside a web component that you can fill with your own