I get this error when browsing list of ideas:

TypeError: href is undefined

Source File: https://www.phpbb.com/ideas/assets/js/ideas.js

Line: 269

Its on last line of function idea_is_duplicate()

That function (or maybe even whole ideas.js) shouldn't be called on page listing ideas. Here is code it is called from:

// Hide duplicate column if status is not duplicate

if (!idea_is_duplicate()) {

	$('.duplicatetoggle').hide();

}