What does this button do in an ArcPro 3.3 script tool?

[DuncanHornby]

With the recent upgrade to ArcPro 3.3 I have noticed a new button that has appeared when defining parameter labels, what does it do? If I add any text to it, then OK the dialogue it is forgotten and nothing appears to be stored anywhere? 

Tagging @KoryKramer , @ShitijMehta 

[DanPatterson]

when you leave the parameter and move away, doesn't a little "i" appear in a circle?

if you move the mouse back over it, a little popup appears which should show the contents of what you typed in there.  Useful for notations

[DuncanHornby]

If you are talking about the popup that occurs when the script tool is running as a tool, rather than me setting properties of parameters as shown in my first question, then yes the blue circle icon appears but nothing shows in the popup. Normally I set the text for those via the Edit metadata > Syntax >Dialog explanation.

What I show in my original question appears to do absolutely nothing, I wonder if it is functionality that they intend to implement in a future version of ArcPro?