[Lexical]

I have long used the Calibre viewer as default for viewing epub, mobi, and some other formats. I now discover that all this time it has been ALTERING the contents of at least the epub books! This is crazy - you never change a source file without explicitly asking!

So every file I've viewed is now different from its original, making a search for and management of duplicates almost impossible.

And yes I now found apparently the one place on the web where someone pointed out the buried Preferences setting to disable this crazy behavior - which is enabled by default because "users prefer it". NO - users don't even know it's happening.