Merge branch 'cherry-pick-4af1d5c2 [formerly 1448b8cdc8]-21.0' into '21.0'

Sweeping !14450 from 21.1-dev to 21.0.
Fix bug whereby a histogram plotted twice would be modifed twice

See merge request atlas/athena!14482

Former-commit-id: 30a95040d185737ce0ed99c61e88f8dc4ac67a1b