Regex Pattern Message

Hi.
I set up a validation rule using pattern as below
/(\d{6}[A-Za-z]{2})(([,]\d{6}\w{2})*)/g

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The pattern field keeps showing the popup message saying enter a valid expression. The expression itself is valid and its working fine on the browser too.
So, is this message just an info/warning or is this a bug?

That’s just an info tooltip which appears when you focus the pattern input.

Ok. It is quite distracting.