Good discussion guys! I see there's a lot of things to think about!
Here's one other example of current Calibre's search problems. I encountered this issue few days ago and I had no idea what was wrong until I spent few minutes investigating.
Say your title (or whatever filed you wish… description filed with rich text is usually the culprit here) uses a proper curly quote, ’ , and not ' as an apostrophe…. as in: "Calibre’s Search". And say you want to search for it and you type "calibre's search" (regular apostrophe). If you followed discussion so far, you're realize that Calibre won't show you the book. But what do you think will happen when you copy paste the exact text string into the search field: "Calibre’s Search"? Will Calibre find it? What do you think? No cheating
This why it's important to strip all these characters out. Someone who's not aware of these issues will never figure out why they can't find anything. When importing books in to Calibre, it shouldn’t feel like I'm putting things into a black hole
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