Is it obligatory to abandon the Sunnah prayers, or is the condition to be considered one of continuous yellowish discharge, knowing that it may appear before and after menstruation but is not continuous with it, and may increase or decrease at unspecified times, and sometimes appears after prolonged prayer, walking, or istinja (cleansing after defecation or urination)?

Yellowish and brownish discharges are considered menstruation if they occur during the regular period or if they are connected to blood at the end of it. The yellowish discharge seen by the questioner is not considered menstruation, but it is impure and necessitates istinja' (washing the private parts). Maliki jurists are lenient regarding impurities that exit involuntarily, although the opinion of the majority, which mandates istinja', is more cautious.

If this yellowish discharge ceases at a known time, allowing for the performance of purification and prayer, then she should wait and pray within that time. If its cessation is irregular and unknown, then her ruling is that of one afflicted by incontinence (sals). She should perform ablution after the entry of the prayer time and pray with that ablution as much as she wishes until that time exits.