In a large framework on which Im working, with horrible setup, jQuery's loaded in some pages but in others: after banging my head a couple of times, went here and read @Nurp answer. Saved my day.
The problem is i am using application that has dependencies on older jquery version and i am not allowed to change and it is being imported later at some stage ! i have used latest version of jquery and then bootstrap js , causing all the problems !
This warning may also be shown if jQuery is declared more than once in your code. The second jQuery declaration prevents bootstrap.js from working correctly.
Very good hint, I had jquery npm installed in Aurelia and also manually loaded in index.html. Thanks!
thanks for this point ,i met this issue and found that my own DataTable.min.js had imported jquery libraries into it ,but my page import it again ,that's the root issue caused it .