Bug report

Bug summary

I'm intermittently getting the warning font family ['serif'] not found. Falling back to DejaVu Sans when plotting with rc('text', usetex=True) enabled. If I delete ~\.cache\matplotlib the warning stops and the charts are rendered with the correct font. But a day or so later it starts again

Code for reproduction

Cannot reliably reproduce as intermittent, can reliably fix by deleting ~\.cache\matplotlib

Matplotlib version

• Operating system: Ubuntu 18.04
• Matplotlib version: 3.0.2
• Matplotlib backend: module://ipykernel.pylab.backend_inline
• Python version: 3.7.1 x64
• Jupyter version (if applicable): 4.4.0
• Other libraries:

installed from pip