Dropdown inline edit throws an error when changing selection with the keyboard

After upgrading jQuery to v3.1 Dropdown Inline Edit throws an error ( lis.size is not a function ) from jquery.selectbox-0.5.js (line 149). This stems from the fact that the size function was removed from jQuery v3.0 ( https://api.jquery.com/size/ ).

Steps to reproduce:

1. Open the Dropdown InlineEdit manual test ( http://build.fluidproject.org/infusion/tests/manual-tests/components/inlineEdit/dropdown/ )
2. Tab to the dropdown inline edit element
3. Press the Enter key to activate it
4. Use the arrow keys to move around
5. Notice that it doesn't change selection and that an error was thrown in the console.

Unfortunately it doesn't seem that the select box plugin is being maintained anymore. I've found a version up to 1.2, but it also makes use of the size function.
http://stackoverflow.com/questions/1072239/is-it-possible-to-style-a-select-box/1072266#1072266

We could do one of the following:

• patch the select box plugin
• find a new plugin
• create our own support for the select box
• stop supporting a dropdown inline edit.