Explorer toolbar and item background color width do not take all space available

[AxelRICHARD]

• I have checked that this bug has not yet been reported by someone else
• I have checked that this bug appears on Chrome
• I have specified the version :

• latest

• I have specified my environment :

• All

Screenshots

Steps to reproduce

1. Create/open the Robot Flow demo project
2. Rename one of the Robot item in the explorer with with a very long name
3. Click on the root document tree item
4. Click on the renamed Robot tree item

Expected behavior

The toolbar takes all the width available, its icons stay on the right.
The selected item's background color takes all the width available.

Actual behavior

The toolbar only takes the min width, its icons do not stay on the right.
The selected item's background color takes the min width.