Do not remove the title bar in maximized windows

[fabianski7]

Symptom If "maximize the solo window" option is active, maximized windows have their title bar automatically removed, this is a smart space saver but can break some workflows.

How to Reproduce

1. Make sure breeze or kwin is not removing the titlebars
2. Install and activate https://github.com/Zren/material-decoration
3. Now the application menus are integrated in the title bar, so they become essential and cannot be hidden

Expected behavior The option to auto remove the title bar from maximized windows should be optional

Environment KDE Plasma Version: 5.21.2 KDE Frameworks Version: 5.79.0 Qt Version: 5.15.2 Graphics Platform: X11

Notes Even if the theme used is not Material, the integrated menus can still be used, as in Breeze itself. They will not be inline, but in a hamburger menu; this is exactly how I use it.

[twifty]

Possibly related. I use the "Global Menu" plasmoid in the dock. When a single window is maximized, the menu options disappear from the dock. It can be quite annoying for those applications which don't provide a inner menu.