Well ... calibre just saved my mind ... and the life of my Paperwhite ....
So, I open a Wodehouse book to read on a miserable rainy day ... and encounter a word I want to look up ... tap the screen ... and a box pops up that tells me that my PW does not have a dictionary installed for the book's language ... and that I need to purchase and install one. Hmmmm ..... I go into settings and verify that I have 2 English dictionaries in place ... and switch from one to the other, in case one has become corrupted or something. And return to my book (a legally purchased book from Amazon - published by WW Norton - and not tinkered with) - and get the same message! Hmmm .... so I try using the Wikipedia look up - which also doesn't work.
Fearing a factory reset, my coffee finally kicks in and I load the book into calibre - and in the metadata the language is set to Arabic. Go figure. Some really great quality control in ebook production, eh?
[Imagine the call to Amazon CS from someone who never heard of calibre, let alone metadata, trying to convince someone that the dictionaries don't work anymore .... getting a replacement PW .... etc ...

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