Possible problem parsing kirbytext within YAML structured field

The field content you posted is no valid YAML:

If a line contains a colon and a space directly following it, the part before the colon is interpreted as the key and the rest as the content. You need to wrap the second line in quotes to force string parsing:

- [Kirby website](http://getkirby.com)
- "(twitter: getkirby text: Follow Kirby on Twitter)"

You can also omit the spaces, but that’s far harder to remember and debug.