Distorted tick labels with matplotlib.animation

With more recent versions of matplotlib I'm getting distorted labels on animated plots. Is anybody else getting this? Am I doing something wrong?

Minimum working example:

from netCDF4 import Dataset
import numpy as np
import matplotlib
import matplotlib.pyplot as plt
import matplotlib.animation as animation
from IPython import display

print(matplotlib.__version__)

# Make a random array of data to plot

r = np.random.rand(10,100,100)

fig, ax = plt.subplots(1,1,figsize=(10,10))

# Initiate Plot

plot = ax.pcolormesh(range(0,100), 
                    range(0,100), 
                    r[0], 
                    cmap='RdBu')

cb = fig.colorbar(plot)
cb.set_label('Temperature')

def animate(frame):
    
    C = r[frame][:-1,:-1]
    
    plot.set_array(C)

ani = animation.FuncAnimation(fig,
                              animate,
                             frames= range(0,r.shape[0]),
                             )    

video = ani.to_html5_video()
html = display.HTML(video)
display.display(html)
plt.close()

My labels seem like they're being placed many times (although this bug persists even when the animation only has two frames), and they appear like this:

This behaviour does not occur if I comment out all the lines below the ax.pcolormesh... which creates static plot that looks fine.

I'm on matplotlib 3.3.2