Button images not visible in Toolbar overflow popup

[mbechev]

Description

In case of displaying an image, instead of an icon, for a Toolbar Button, the image is not displayed inside the overflow popup of the Toolbar:

Screenshots

Image Button in Toolbar:

Button in overflow popup:

Steps to Reproduce

Example:
https://stackblitz.com/edit/angular-njdfrtjj-ckyqsgr1?file=src%2Fapp%2Fapp.component.ts