The following code, taken from the examples in root_lattice_realizations.py, produces a plot with messed up labels, which contain raw latex code blocks

sage: L = RootSystem(['A',2]).ambient_space()
sage: C = crystals.Tableaux(['A',2], shape=[2,1])
sage: L.plot_crystal(C)

Found when testing matplotlib 3, which gives a warning here due to bounding box overflow

CC: @timokau @kiwifb @tscrim

Component: packages: standard

Keywords: matplotlib

Issue created by migration from https://trac.sagemath.org/ticket/28449