Overflow Menu button doesn't appear in Sidebar When Single Toolbar Mode is Active

[mu7basha]

Preliminary Checks

• I have read and understood the important section above.
• I have searched existing issues and avoided creating duplicates.
• I am not filing an enhancement request.
• I have checked that this issue cannot be reproduced on Mozilla Firefox.
• I have checked that this issue can be reproduced once I removed all my Mods and Custom CSS.

What happened?

When The Browser layout is set to 'Single Toolbar' in Settings, The Overflow Menu doesn't appear, even if there were Items in the menu. However, in The other two Modes, The Button appears Normally

Expected behavior

The Overflow button should appear in The sidebar When there is Items inside it While The Browser layout is Set to 'Single Toolbar' Mode

Actual behavior

I added some Items to the Overflow Menu, but the Button doesn't appear in Single toolbar mode, Other Browser layout options have the Overflow Menu Button.

Steps to reproduce

1. Go to Settings > Look and Feel > Browser layout, Then Select 'Single Toolbar' Option.
2. Right-Click Zen's Sidebar, Then Select 'Customize Toolbar' Option.
3. Add Items to the Overflow Menu, then Press 'Done' Button.

Screenshots and videos

Version

1.13b

What platform are you seeing the problem on?

Linux (Flatpak)

What component is this issue related to?

Customizable UI / Toolbars

Relevant log output if applicable