神坑

Calibre E-book viewer > Preferences > General > Miscellaneous options:
Keep a copy of bookmarks/current page inside the ebook file, for easy sharing

calibre_ebook_viewer.png

上面选项的意思是:

Keep a copy of all bookmarks/current page information inside the ebook file, so that you can share them by simply sending the ebook file itself. Currently only works with ebooks in the EPUB formats。

一定要把上面这个选项去掉,否则,Calibre E-book viewer 会在你查看 ePub 文件时自动向你的文件中加入 bookmarks/current page information,从而改变你的 ePub 文件的内容和大小。一个 E-book viewer 竟然改变文件的内容和大小,而且还是个默认选项,简直逆天了。

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