Saving with current master and a password removes all content from the document. It is not the import as the calc import tests still work.
Added LO-3.7 into the subject, so it is easier for me to filter LO-3.6 blockers :-)
Some more comments from debugging and exploring:
content.xml and styles.xml look the same between unencrypted and encrypted export
manifest.xml looks normal but did not yet check against a 3.6 file. No exceptions during export or import are thrown that look wrong.
Ok, looks like http://cgit.freedesktop.org/libreoffice/core/commit/?id=9b0198b2442bc749491d0f1e5e2c811346e5d568 broke it. I have to figure out why it only broke the encrypted document import.
This was a problem around uno. The commit introducing support for larger streams changed all the stream size variables to 64 bit but the one place where these information are written into the manifest.xml was still 32bit. UNO therefore did not write the information into the variable.
Markus Mohrhard committed a patch related to this issue.
It has been pushed to "master":
uncommpressed stream size is now 64bit, fdo#56291
The patch should be included in the daily builds available at
http://dev-builds.libreoffice.org/daily/ in the next 24-48 hours. More
information about daily builds can be found at:
Affected users are encouraged to test the fix and report feedback.