How to do filename completion with umlauts?

[Andy Spiegl <zsh.Andy@xxxxxxxxx>]

Hi,

how do I make case-insensitive filename completion work with umlauts?
I tried
 zstyle ":completion:*" matcher-list 'm:{A-Zöäüa-zÖÄÜ}={a-zöäüA-ZÖÄÜ}'
but it doesn't work.

Thanks!
 Andy.

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                              o      _     _         _
  ------- __o       __o      /\_   _ \\o  (_)\__/o  (_)          -o)
  ----- _`\<,_    _`\<,_    _>(_) (_)/<_    \_| \   _|/' \/       /\\
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