Nobody cares perhaps, but F5 as a refresh key came in the mid 80s (I was told it was a $1m of usability consulting). The midrange AS/400 got [CUA](https://www.ibm.com/docs/en/zos/3.1.0?topic=actions-default-...) first. There were many more F1 for help, F12 for go-back-a-page, F3 for big-exit of app. Green screen stuff (3270 and 5250 where two common wire/frame protocols). The same keys made the jump to some windows apps. One by one they got whittled away until F5 for refresh was left. For that one it wasn't just Windows - as browser rollout took it wider. Has it gone yet? I'm on a Chromebook and it doesn't have F keys so I can't see for myself.