The wiki entry for Dictionaries states:
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Dictionary names start with a alphabetic character, followed by any number of alphanumeric, space or underscores. Dictionary names are case insensitive.
Key names can be anything, although leading and trailing white space is stripped off. Key names are case insensitive.
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I'm trying to use a key name that contains a forward slash, e.g. this/name, but it seems that only the first part "this" is actually being used by KM.
So the question is: can they really be anything?