TinyWiki has a class called TWSmiley. Your WeatherPI code link leads to a page that is activating TWSmiley class>>#binaryShocked four times. 
That is to say, every time the parser sees :0 it creates a round, blue gif of a shocked smiley. When you write in code {0:0.2f} the third and fourth characters are replaced with a blue smiley face. 
Adding a space after the colon would probably fix that. 
I guess Lukas Renggli was in all ways younger in 2004. 

http://www.squeaksource <http://www.squeaksource/>.com/WeatherStation

Chris 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/squeak-dev/attachments/20170402/8ed47c02/attachment.html>