I working on this template >> https://lordofthemysteries.fandom.com/wiki/Template:Char_temp
And had made a "collapsible" in "Vital Status" field.
It's work, however, I want to add "Killed by" and "Cause of Death" field only appear when click [Expand] on "Vital Status" field too. Is it possible and how to do it?
Why did you put a div in a format in a portable infobox? You can achieve this much better and cleaner if you use the regular group tag. See how the code on the other sections, like "Relationships" looks? Instead of "open", use "closed" and it's collapsed on default. Make sure to close the group and then create a separate group/header for Species/Hair C/Eye C.