Because our Inspect tool uses an overlay and the cursor to view the CSS elements, some style effects like MouseOver and MouseDown are temporarily unable to activate the alternate style while in the Inspect mode.
However, style effects that are able to leave the widget in this state (like Selected or Disabled) are still able to be picked up by the Inspect tool.
It does look like our product team has been looking into a feature that will allow style effects like Mouse Over to be able to be registered when Inspecting. I have gone ahead and added your request to the ticket to let them know that more users are interested in this feature and hopefully, it can gain more traction.
In the meantime, if you wish to see those style effects when inspecting, something you can do is pair those style effects with another one that is able to be toggled. For example, if you pair a MouseOver and an Error effect using the same style, you can use an external button to toggle that Error state. You can also set the effects using the Widget Style Manager to make things easier. I have included my sample .rp file demonstrating this. Style Effects.rp (46.1 KB)