Reopening this, seems like things regressed and even got worse.
- Go to Admin → Settings → Basic Setup →
suggested topics
Firefox on desktop
- Enter 5.0 then save (no error) and refresh → Find it has been set to 50
- Enter 5,0 then save (no error) and refresh → Find it has been set to 0
Safari on iOS
- Enter 5.0 then save (no error) and refresh → Find it has been set to 50
- Enter 5,0 then save (no error) and refresh → Find it has been set to 50