Bootable 64-bit Gentoo image for the Raspberry Pi4B, 3B & 3B+, with Linux 5.4, OpenRC, Xfce4, VC4/V3D, camera and h/w codec support, weekly-autobuild binhost
What type of display are you using? You may need to edit /boot/config.txt: try in the first instance commenting out the line disable_overscan=1 (and then rebooting).
Its like it doesnt fit the screen. The menu bar and launch bar are out of view, only partially visible. Display settings in xfce do not offer solution