SimpleJekyllSearch / jekyll-search.js is throwing errors (v4)

Created by: petetnt

Bootstrap (/), Documentation and Examples-pages are throwing this:

Uncaught ReferenceError: se is not defined
   (anonymous function) @ jekyll-search.js:1

and as (/) and Examples don't contain a search input element, they are also throwing a searchInputthrowError :

jekyll-search.js:1 Uncaught Error: SimpleJekyllSearch --- You must specify a searchInputthrowError 
  @ jekyll-search.js:1validateOptions
  @ jekyll-search.js:1self.init
  @ jekyll-search.js:1(anonymous function) @ (index):292

(Searching does seem to work properly on the docs page however)