What is the ruling on one who suffers from urinary incontinence, and drops of urine continue to trickle after performing ablution, despite being certain that all urine has been expelled and the area has been cleansed?

If the criterion of سلس (incontinence) applies to you, then take precautions (wear a pad, etc.), perform ablution after the time for prayer has begun, and pray. What exits from you will not harm you. Complete your ablution if urine exits during it. However, if the criterion does not apply to you, then wait for the urine to stop, then perform ablution and pray. Istinjā’ (washing away impurities) is obligatory to remove the impurity, unless it becomes exceedingly difficult for you, in which case it is permissible to act upon the opinion of the Mālikī school, which does not require its removal.