Leaf changing color?

This is my white widow 5 weeks old I have one leaf changing color on the whole plant any ideas? Grow lights are on in this picture

Natural light pictures will help diagnosis

yes , was thinking the same thing… up loading now

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Looks like possible light bleaching @NeoGroR I think you were a blurple guy once upon a time , your opinion?

Tbh, I’ve neve had a bleaching issue and I don’t know what causes it. Sorry I couldn’t be of any help