It is helpful if you give the actual version of the dashboard. This could help someone in the future since the version could change at any time. You should also provide the Node-RED and node.js versions. All three of these are displayed in the node-red startup lo making it easy to copy and paste them.
Is the led node of the same dashboard tab as your other ui nodes? Can you provide a copy of your flow?
In order to make code readable and usable it is necessary to surround your code with three backticks (also known as a left quote or backquote ```)
```
code goes here
```
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See this post for more details - How to share code or flow json
