Behavior of Trim tool

When I use the Union tool, I can continue to select items and union them together.

When I use the Solid tool, after using it once, I cannot continue to select anything else. I must re-press the hot key for it.

I remember it not being like this in a previous version of Sketchup. Can you please switch it back so that the Trim tool allows me to continue using it until I am ready to switch operations?

Thank you for the consideration.