In boiling soapy water, globs of soap coalesce as the temperature increases to boiling. Does this mean that temperature increases the gravitational pull of bodies?
Your question has nothing related to the gravitational force. Gravity (as far as we know) is very very weak. When at some higher temperature, the bubbles simply follow a randomness (brought out as a thermodynamical law called entropy). I mean, the bubbles just randomly go around everywhere and there's a higher probability for many to pop when heated. There's also this probability for some bubbles to merge together (which may appear as they coalesce) and pop. Anyways, the result is popping..!