Inline variable preview javascript debugger firefox oddity

you’ll see in the two attached pictures that in one the degrees variable is declared outside the function and initialized to null. After it is assigned a value inside the function the inline variable preview doesn’t work on it. In the other picture the variable is declared and initialized inside the function and the preview does show its value. Why does the debugger do this?
Thanks for any help,

You’re… showing us pictures in which the degrees variable is defined in both pictures.

In your first picture it has a value of 50.
in your second picture it has a value of 25.

Do you mean the angle variable? That one is defined without value in your first picture, but the function you’re showing hasnt set or assigned a value to angle.