The white arrow in attached image, what does it mean? I use Windows and there is no tool tip with info.

The white arrow in attached image, what does it mean? I use Windows and there is no tool tip with info.

That small squiggle arrow is indicating that the object has an action. Meaning that the object is animated.
If you click on the plus button and open up the hierarchy you will see that it is an animation.

Ok to get rid of these icons (which indicate an action), right click it and pick "UNLINK ACTION". Either before this or after open the ANIMATION VIEW -> CLICK the Object and then delete the action from the animation layer too.