Browsing around in VisualEditor with <https://gerrit.wikimedia.org/r/322812> applied:
### Breaking
> JQMIGRATE: jQuery.fn.removeAttr no longer sets boolean properties: required
> https://jquery.com/upgrade-guide/3.0/#breaking-change-removeattr-no-longer-sets-properties-to-false
Stack: `OO.ui.TextInputWidget.setRequired / .. / ve.ui.MWReferenceDialog.initialize`
When: Opening Reference insert dialog.
Stack (2): `OO.ui.TextInputWidget.setRequired / .. / ve.ui.MWSaveDialog.initialize`
When: Saving changes.
> JQMIGRATE: jQuery.fn.offset() requires an element connected to a document
> https://jquery.com/upgrade-guide/3.0/#breaking-change-invalid-input-to-the-offset-method
Stack: `jQuery.fn.offset / $.fn.position / .. / mw.widgets.MediaSearchWidget.lazyLoadResults`
When: Selecting an image from results in Media insertion dialog.
> {icon exclamation-triangle color=red} Uncaught TypeError: Cannot assign to read only property 'left' of object '#ClientRect'
Stack: `Object.OO.ui.Element.static.getRelativePosition / .. / OoUiPopupWidget.OO.ui.PopupWidget.setAlignment / VeUiDesktopContext.ve.ui.DesktopContext.updateDimensions`
When: Selecting text and creating a link
When (also): Double-click an HTML Comment node in the surface for editing.
After this the inspector can't be closed and most surface interactions are broken.
{F6678336}
### Deprecated
Will not be removed in jQuery 3.0, but warned for as long as jQuery Migrate enabled.
> JQMIGRATE: jQuery.expr.filters is now jQuery.expr.pseudos
> https://jquery.com/upgrade-guide/3.0/#deprecated-jquery-expr-quot-quot-and-jquery-expr-filters
Stack: `OO.ui.isFocusableElement / .. / ve.ui.MWMediaDialog.initialize`
When: Opening Media insert dialog