Thanks, Tex, but I tested the .epub with
Code:
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
instead of
Code:
<html xmlns="http://www.w3.org/1999/xhtml" lang="en-US" xml:lang="en-US">
And when I ran Flight Crew, there were no errors, so it would seem to me that is optimal. Is there a reason you think
Code:
<html xmlns="http://www.w3.org/1999/xhtml" lang="en-us" xml:lang="en-US">
is preferable to
Code:
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
?