When must a woman perform ghusl if a yellowish-white discharge, which may also occur outside of her menstrual period, appears after her period has ended?

A woman who experiences blood discharge, followed by brownish (kudrah) then yellowish (sufrah) discharge, attains purity (tahara) through the "white discharge" (al-qassah al-bayda') or dryness. If the dryness persists for a full day, then it is purity. If she is accustomed to a specific duration for blood, brownish, and yellowish discharge (e.g., seven days), and then dryness appears, she must perform ghusl (ritual bath) and pray, and not wait for a full day. If she sees purity, and then brownish or yellowish discharge appears, it is not considered anything unless blood reappears, based on the saying of Umm Salamah: "We did not consider brownish or yellowish discharge after purity to be anything." The woman determines her habit. A woman with an irregular period waits for purity or fifteen days, then performs ghusl and prays. A woman with a regular period follows the detailed explanation provided.