Yes, you can connect multiple Roku units to a single Roku account. Your channels are attached to your account, not to your device, so the new Roku should automatically install all your current channels. Add/delete from one, you add/delete from all. Any channel's that require a log in will need to be logged in on the new unit.
You may find some newer channels that won't install on your older unit because it doesn't have the power to run them.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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Streaming Stick 4K+ 3821 | Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X
