This is the way to check if your RPI4 is running the latest firmware.
You need to do this using ssh
If you don’t know how to use that, this is not for you
sudo -s
cd /tmp
apt update
apt -y install pciutils
wget https://archive.raspberrypi.org/debian/pool/main/r/rpi-eeprom/rpi-eeprom_16.1-1_arm64.deb
dpkg -i ./rpi-eeprom/rpi-eeprom_16.1-1_arm64.deb
#now run the program:
root@neon:/tmp# rpi-eeprom-update
*** UPDATE AVAILABLE ***
BOOTLOADER: update available
CURRENT: Tue Jan 25 02:30:41 PM UTC 2022 (1643121041)
LATEST: Wed Jan 11 05:40:52 PM UTC 2023 (1673458852)
RELEASE: default (/lib/firmware/raspberrypi/bootloader/default)
Use raspi-config to change the release.VL805_FW: Using bootloader EEPROM
VL805: up to date
CURRENT: 000138a1
LATEST: 000138a1
In my case the firmware is up-to-date (important because of thermal issues, see Raspberry Pi 4: New Firmware Reduces Power Consumption and Board Temperatures | Geeks3D)
I am not as much interested to update the bootloader, since it is working as expected.
If there would be newer firmware available
rpi-eeprom-update -a
followed by a reboot would take care of an update.