Is a girl who suffers from a menstrual disorder and experiences continuous, almost regular yellowish discharge after purification—such that she often sees it during prayer times—and finds it difficult to maintain purity, perform ablution, and clean herself for each prayer, and has difficulty determining when it stops, considered to be in the state of istihadha (non-menstrual bleeding) or suffering from سلس (incontinence/continuous discharge)? And is it permissible for her to pray with her ablution if the yellowish discharge appears? And is it permissible for her to combine two prayers out of necessity or when leaving the house and fearing that her ablution might break, especially since she suffers from obsessive doubts regarding ablution?

What you observe of a persistent yellowish discharge throughout the month is considered istihadah (non-menstrual bleeding), and you must perform ghusl (ritual bath) after the cessation of blood, not counting any of this yellowish discharge as menstruation. Since the cessation of the yellowish discharge is unknown, you are among those with a perpetual state of impurity (hadath da'im), and you must perform wudu (ablution) for each prayer after its time has begun. You may pray as much as you wish with this wudu until the time for the prayer expires. It is permissible for you to combine two prayers. According to the Maliki school, the wudu of someone with a perpetual state of impurity is not invalidated except by a voluntary (ikhtiyari) impurity-causing event, and this is a strong opinion that may be adopted when necessary.