Glass theme is not working in windows

[SalahAdDin]

Describe the bug
The glass theme for the toolbar is not working in Windows (with the Cupertino theme).

To Reproduce
Steps to reproduce the behavior:

1. Go to Options
2. Click on Editing Toolbar
3. Go to Appearance and look for the Toolbar Theme option
4. Choose glass

Expected behavior
It should look glassy.

Screenshots

Desktop (please complete the following information):

• OS: Windows 11 Home (24H2) x86_64
• Browser: Firefox 147.0.3 (64-bit)
• Version: 1.11.7

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
We reported this issue before in the theme (Cupertino) here.