I know that a number of big sites do this now, but I don't think that having an indicator that goes in a different direction that the scrolling (horizontal vs vertical) is all that intuitive.
Is there even consensus as to what this type of indicator means?
For example, anything developed with Quasar Framework will by default show the same thing to indicate the progress of background Ajax request...
Perhaps this is a job better left to the scroll bar?
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