Make Fragmenter more robust regarding swapped offsets.
Make Fragmenter more robust regarding swapped offsets.

andene/substance,jacwright/substance,substance/substance,abhaga/substance,TypesetIO/substance,podviaznikov/substance,substance/substance,jacwright/substance,abhaga/substance,michael/substance-1,michael/substance-1,andene/substance,podviaznikov/substance,stencila/substance,TypesetIO/substance