Kibana 7.16.3 in latest Firefox and Brave (chromium) browser
Steps to reproduce:
- app/visualize
 - create
 - aggregation based
 - line
 - select a saved search
 - aggregation: percentiles
 - field: any number field
 - bucket: add x-axis
 - aggregation: date histogram
 - update
 
If you adjust aggregation to count, the y-axis labels are visible again.
Note: Existing percentiles visualizations are still working correctly.


