Norwegian/Danish national characters mess up post slugs

[dnusim]

When the post slug is generated from the post title, the letter 'Å' 'å' converts to 'a', should convert to 'aa' which is the general practice in countries using this character (Confer ​Wikipedia).

Furthermore, the Norwegian/Danish characters 'Æ' 'æ' and 'Ø' 'ø' should be converted to respectively 'ae' and 'oe'. As of now, these convert to '%c3%a6' and '%c3%b8'.

Some may consider this a dupe of #4739.

[westi]

This is definitely a dupe of #4739.

Closing as such

[hansengel]

Westi, you forgot to close it :P