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Legacy Bios, UEFI and SecureBoot ready Ubuntu Live image customization
This article will provide you with a core information on how to create boot-able Ubuntu Live customized isohybrid image to get you started with your own Ubuntu distro spin-off. The output image will be amd64 customized Ubuntu live image, capable to boot in all three boot modes: Legacy Bios, UEFI and SecureBoot.