The generated extension headers maintained an ordered list of older extensions to minimize diffs with the non-generated extension headers, but there is no reason to require this for new extensions. If a new extension is not found in the list, sort it at the end automatically. Note, Khronos (KHR) extensions will also be sorted before multi-vendor (EXT) extensions, and before vendor extensions.
The generated extension headers maintained an ordered list of older extensions to minimize diffs with the non-generated extension headers, but there is no reason to require this for new extensions. If a new extension is not found in the list, sort it at the end automatically. Note, Khronos (KHR) extensions will also be sorted before multi-vendor (EXT) extensions, and before vendor extensions.