So, what happens to all the extra mass a star has? All the planets are much smaller in mass than even small mass stars.
The mass was never there to begin with.
1. True mass of "Sun" is 2.82 * 10^23 kg based off density measurements of photosphere in accordance to homogeneous sphere as based off measurements of global harmonic oscillations (helioseismology recordings) of 2 hours and 40 minutes and its moment of inertia as a celestial sphere of .059, meaning it is undifferentiated.
2. True mass of "Sun" is 3.61 * 10^23 kg based off empricial measurements of tidal force exerted by the Sun as opposed to the Moon, which is roughly 2.21 times as strong, using Newton's equation for Force = G((M1m2)/d^2).
Both of these mean the Sun is very diffuse ball of plasma. It is not the supermassive 333,000 times the mass of Earth ball mainstream has taught based off mathematical models for the supposed requirements for stellar fusion. Hydrogen fusion is simply not happening in the sun. It resemble an arc welding torch more than an nuclear furnace. It should be no surprise that the surface is around the same temp as an arc welder.