This is one case where you really need to report what Roku model your are talking about, as some just use a standard USB micro cable that runs from the Roku to a USB power adapter, while others have dedicated power supplies with attached cords that connect to the Roku via a round connector.
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Streaming Stick 3600
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