When you look at the help page for creating timelines at the end of the paragraph, the blue text overlaps with black text, making it unreadable:

https://en.wikipedia.org/wiki/Help:EasyTimeline_syntax#Text_attributes (scroll down a little bit)
or on the same help page:
https://en.wikipedia.org/wiki/Help:EasyTimeline_syntax#Clickable_maps

In 2009 this worked fine, as you can see here:
https://web-beta.archive.org/web/20090320015610/http://en.wikipedia.org/wiki/Help:EasyTimeline_syntax#TextData
https://web-beta.archive.org/web/20090320015610/http://en.wikipedia.org/wiki/Help:EasyTimeline_syntax#Clickable_maps

Same with other languages,
https://de.wikipedia.org/wiki/Hilfe:Zeitleisten#Eingebettete_Links

I expect the examples on the help page to work …