Hi @Kentin_RDG ,
Thanks for your post and welcome to the Cesium community.
This previous post here Change Timeline from UTC to Local Time - #3 by omar shows how you can override the timeFormatter
or dateFormatter
functions which take a date/time and return a string that appears in the clock widget. Can you use that as a template to get the date format you are looking for.
Please let us know and we are happy to try to help more if needed.
Best,
Luke