Is the white discharge with a very slight yellowish tinge, or the clear discharge with some whiteness, considered a sign of the white discharge (al-qassah al-bayda') indicating purity from menstruation?

The white discharge indicates the end of menstruation, but not all women see it. Many women recognize purity by dryness, meaning the cotton swab comes out clean, without any trace of blood, yellow discharge, or brownish discharge. White moisture does not harm. If the yellow discharge is connected to blood, then the woman is menstruating. But if she sees dryness, she has purified herself and must perform ghusl (ritual bath) and pray, and she should not pay attention to any yellow or brownish discharge that comes after that.