On the Constructed Worlds Wiki for over a month now, the wiki's collapsible elements (show/hide function) has stopped working and no longer appear. The wiki utilizes several templates which rely on this function (namely navboxes) and has forced us to manually expand each template in order to show their contents. We have asked for assistance on this issue before to be told that it can be resolved by fixing our common.css page's code. However, we have already tried multiple iterations from other wikis, including other Miraheze wikis, to test and see if the collapsible elements would re-appear to no success at all. Prior to the disappearance of the collapsible elements (which happened around November 8), we did not do any changes to the .css at all (it was last edited in 2018), the .js, or implement any wiki extensions which could have possibly caused this. We would like to resolve this issue because it has been a major quality of life problem.

Common.css page
Common.css history

Example of broken templates:
Template:Sierra (standard navbox with non-functioning collapsible option, forced to expand in code)
Template:Derzhavism sidebar (standard collapsible sidebar with non-functioning collapsible option, expanded automatically)