Request: Add Support for Client-Side Decorations (CSD) / Titlebar-Less Windows

[genefyx]

It would be great if Stremio supported Client-Side Decorations (CSD) or an option to run without a titlebar. This feature is particularly useful for Wayland users, as it allows for better integration with modern desktop environments like GNOME, KDE, and others.

Reason:

Many Wayland users prefer a titlebar-less experience for non-maximized windows.
Qt provides APIs (e.g., Qt::FramelessWindowHint) for developers to implement custom decorations or remove titlebars entirely.
CSD aligns well with the modern design language of GNOME and other compositors.

Suggested Implementation:

Use Qt::FramelessWindowHint to allow users to toggle titlebars.
Alternatively, provide an environment variable (e.g., STREMIO_DISABLE_TITLEBAR) or a UI setting to enable/disable decorations.

Benefits:

Improved appearance and integration with GNOME/Wayland setups.
Greater flexibility for users who prefer a clean, frameless look.

References:

Qt Documentation on Custom Window Decorations: https://doc.qt.io/qt-5/qt.html#WindowType-enum
Wayland's xdg-decoration protocol for compositor negotiation: https://wayland-book.com/xdg-shell-basics/xdg-decoration.html

Thank you for considering this feature request!