No idea. Working fine on my setups...
Could be due to the template. Not sure.
Can you see if you get the same issue when using the cassiopeia template (just add ?template=cassiopeia to the url) and assign that module to a position that template has (ie sidebar-right)?
Can you give me (super) admin and (s)ftp access so I can take a look?
You can use the 'Confidential information' button in the forum editor to hide sensitive information.
What extension are you using to minify the html?
I think that that is causing the issue.
Quick Index inserts html comment tags around the index so it knows where to find it after it is rendered. And can then move it to where you have the {index article=“current”} tag.
It looks like something else is removing those html comments before Quick Index has the chance to search for them.
Does this mean that QuickIndex is not compatible with certain other extensions?
I will investigate this according to your specifications and hope that the problem can still be solved in this way.