Another problem that I came across is my tv monitor HDMI seemed to stretch the desktop off the screen.
Since I have the Pi 3 plugged into another port on the same TV and the desktop is fine I knew it was something with the Pi 4.
With a quick google lookup I found an article on turning off GL in Raspi-Config.
Interesting, though it seem simple it is slightly confusing.
This did however fix the problem.
Run sudo raspi-config
Using the arrow keys select 7 Advanced Options
Next using the arrow keys select A7 GL Driver
You will see two selections but only pick the first one and select OK.
You should receive a message that GL has been disabled.
You will also be prompted for a reboot.
Reboot the Pi 4 and your screen should fit as expected, or at least it did for me.
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