Hello there. I have just completed the creation of an RHEL 8.3 booting iso usb drive using Rufus. Everything worked smoothly in ISO mode. Did you use the most recent edition of Rufus (3.13 from November 20, 2020)?
I used Rufus version 3.13.1730.It looks like the installation is going well, but After the language selection screen, the USB media does not appear in the "Installation Source" on the installation screen, and "Software Selection" is not activated unless RHN is registered.It always occurs in UEFI or Legacy bios mode. I tested it on multiple computers and all showed the same symptoms.
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