Thanks @aude
I did like you suggested but it does not seem to solve the issue of improper spacing of non uniform dates. Did I miss something?

Hi.
I had the issue before.
I can reproduce the problem on w:fr and w:en on condition that I am logged in.
If I am not logged in, the w:en editor behaves differently, I cannot switch to the editor after editing the wikicode without having to "leave the page" and thus lose the modifications.
Not sure if this is due to my preferences.
Thanks
Lew

thanks