It looks like you can produce it at will so create a small flow - maybe a couple infect nodes with the data and your ui-template node.
Once you verify it causes the error, export the flow and attach it to a response so someone can try to reproduce it.
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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icon.
See this post for more details - How to share code or flow json
Note: unfortunately it won’t be me since I’m at a location with no node-red available 
