The OEM links on the EdgeRouter-4's page (https://openwrt.org/toh/ubiquiti/edgerouter_4) link to non-existing or unrelated pages.
OEM device homepage URL links to their store with hardly no information about the device.
I suggest it should be set to: https://help.ui.com/hc/en-us/sections/360008075214-EdgeRouter
Firmware OEM Stock URL links to a 404 page.
I suggest it should be set to https://ui.com/download/releases/firmware