Created attachment 139500 [details]
EPUB test file
The whole EPUB packaging system is made to minimize the need to download the whole zip before testing/opening the ebook. That's why the mimetype file MUST, per spec, be uncompressed at first position in the zip. Since finding a given rendition goes through the container.xml file, it would be better if it was stored in 2nd position in the zip instead of the last one as it is now.
See attached epub file generated by Version: 22.214.171.124.alpha0+,
Build ID: 3171066a959b52cd483bb22a0d1046e633f092f6
Unzip -t it.
Similarly, it's better if content.opf comes next, content document right after, and the rest of files at the end.
Build ID: acd16c7e29c1619986d4d8b3b520da089ba34660
CPU threads: 4; OS: Mac OS X 10.13.3; UI render: default;
Locale: fr-FR (fr_FR.UTF-8); Calc: group