mpl.gca(), close() leaks memory

I noticed that the memory consumption of a long-running program increases to the point where it crashes. I've boiled it down to

import matplotlib.pyplot as plt
import time

while True:
    time.sleep(0.1)
    plt.gca()
    plt.close()

Let it run, and watch the memory consumption of the process increase. This is with matplotlib 3.5.3.

What's the reason for this?