Steps to repro:
1. Take the tour until the end, but do not use the Finish button to close
2. Keep going back in the tour by clicking Previous (not sure that this is necessary)
3. Use the Close button to close the tour.
After this, the left panel does not close, no matter what you do (click on the hamburger, click outside)
However, links in the panel work, so you can click one of them to get out of the situation.