breakpoint on parameter

[Matt Maier]

I want to find out which parts of my code are making changes to a control's
parameter. Specifically, I've got an arrow that I want to be black, and it
is black when it's created, but then it turns gray. I can't find the script
that's turning it gray.

I don't know where to put a breakpoint in the script.

Can I put a breakpoint on that control's color parameter, so execution
stops whenever something modifies it and goes to the script that's doing
the modification?