Bug report

Bug summary

Starting from an empty plot (plot()), after alternating a couple of times of zooming interactively and clicking on the "back" button, some ticks disappear. Sorry, I don't have a proper reproducer right now, will investigate.

Code for reproduction

tbd

Actual outcome

Expected outcome

Matplotlib version

• Operating system: fedora
• Matplotlib version: master
• Matplotlib backend (print(matplotlib.get_backend())): qt5agg
• Python version: 37
• Jupyter version (if applicable): no
• Other libraries: no (python -c "from pylab import *; plot(); show()")

I'm not actually sure it's a regression in master (not so easy to bisect without a consistent reproducer :)), but it looks like one and it'd be a pity to release 3.1 with this bug, so tentatively marking as RC...