Unless some bored folks will come up with a separate "strict OOXML" export filter for LibreOffice which attempts to follow the ISO standard to the letter :-)
Posted Jan 12, 2011 8:20 UTC (Wed) by shmget (subscriber, #58347)
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And such patches would most likely be accepted.
Actually they would be a nice addition to illustrate the difference with the so called OOXML 'standard' and the MSXML format that is really in use in Redmond