My computer logs me out ("crashes") when I try to plot using the TkAgg backend (see example below). I am using mojave 10.14.6 and python 3.7.3.
from sys import platform as sys_pf
if sys_pf == 'darwin':
import matplotlib
matplotlib.use("TkAgg")
x = [1,2,3]
# up to here the code does not cause a crash
plt.figure()
pl.plot(x)
plt.show()