Issue with editing a group or a symbol

Hello,
A have a simple but very annoying problem.
I use any drawing tool, and then I group it or convert it into a symbol. Right, very simple, the base !

BUT for some reason I can't explain, when I double-click on it to edit it, the rest of my composition is not shown in low opacity as usual (I'm sorry for may bad english, I hope you will understant what I mean).
For exemple I draw a character with black strokes, on a black strokes background. Then I want to edit my character by double-clicking it. But the strokes of my background remain black, which makes very hard to edit my character comfortably.
Do you have any ideas ? I've already tryied to relaunch Animate and also my computer, Animate is up to date…