I tested the reported scenario, but I was not able to reproduce any error in the RadColorEditor control. When you enter an invalid hex color string in the input field, the color is coerced and reset to #00000000.
I used the following color editor definition to check on your case:
Can you please let me know if I am missing something? Also, it would be helpful if you can provide me with more details on your implementation and a runnable code that demonstrates the issue.
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