Dedoimedo published a tutorial showing how to improve the default look and feel, ergonomics, functionality and behavior of the MATE desktop on top of Raspberry Pi OS on Pi 4.

RPI4, Raspberry Pi OS and MATE desktop - Essential tweaks

Long, detailed tutorial showing how to improve the default look & feel, ergonomics, functionality and behavior of the MATE desktop on top of Raspberry Pi OS on Pi 4, covering desktop environment installation, additional software, new visual themes and icons, black fonts, dock transparency, default desktop environment via lightdm configuration, full-screen Brisk menu, global menu, no video playback in full screen VLC, theming for VLC, LibreOffice and Pidgin, video tearing, Firefox ESR & mobile pages, resolution & overscan, hardware acceleration, Network Manager & Wireless scanning, some other essential tweaks, and more

RPI4, Raspberry Pi OS and MATE desktop - Essential tweaks