Inconsistent coloring of script members

[KoBeWi]

Tested versions

Reproducible 4.5 beta1
Not 4.5 dev5

System information

W10

Issue description

I noticed some variables in my scripts are getting colored with a different color (which seems to be text_editor/theme/highlighting/member_variable_color). The problem is that the color is not applied consistently.

CimGp6MzfK.mp4

When you add a new variable, it uses default color until you reload the script. I think I also had a few cases where a variable had different colors in different places.

Steps to reproduce

1. Add a member variable to your script
2. Reload the script
3. Add another member variable
4. Compare colors

Minimal reproduction project (MRP)

N/A

[akien-mga]

CC @dalexeev @HolonProduction