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As a general rule of thumb, you can override any page or API in the default asset extension pages or apis directory.
Can I override an existing global API?
No, you can not override an existing API. However, if needed you can create a new API, which is globally accessible. For more information, see Adding a New Global API.
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Questions regarding locations of key ES files and directories
Where should I define the RXT definition for a new asset type?
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