I have a question regarding different versions of jquery in Plone 5.2 (I think it's also applicable for Plone 5.0 and 5.1)
We have an static HTML + CSS + JS theme provided by an agency that uses latest bootstrap 4.1.x and jquery 3.3.1. When integrating the theme into Plone, we have prepared a Diazo theme and the site is OK for anonymous users.
Nevertheless, if I login to the site things start breaking because this version of Plone ships with jquery 1.11, and thus it's needed for the toolbar to work or to make the Plone mockup patterns work. After seeing that, we enabled the Plone provided JS files only for admin users, but now we have clashes between the 2 versions of jquery.
I can disable the frontend jquery version, not to show it when logged in, but some features of the site may not work correctly.
Has anyone faced something similar? How have you solved it?