Hi @john john Pter ,
When you create a new library, you can get a list of Office document templates to choose from. They are displayed on the +New button along with folders and links.
After adding custom content type, the default content type is shown and the previous office templates hidden. This is By design.
You can show the hidden Office document templates by clicking on "Edit New menu" and then checking the box.
The custom content type you create called "Custom Document" is created based on the built-in Custom Document content type.
When you create "Custom Documents", you can create it based on characteristics that you define, such as specific templates, specific metadata, and so on. it can be created with characteristics that you define, such as specific templates, specific metadata, and so on.
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