# 3.x Upgrade Guide Version 3.x features a redesigned Month Picker menu which: 1. Looks more consistent with [jQuery UI Datepicker](https://jqueryui.com/datepicker/). 2. Turns the Year title into a button which gives the user a "hint" about the Jump Years menu when they mouse over it. 3. Allows the user to return to the year they clicked Jump years at. See it for yourself at the [demo on JSFiddle](http://jsfiddle.net/kidsysco/JeZap/). An upgrade from an older version is simple, and in many cases only requires a new download. ## i18n property name changes If you changed out the buttons, labels or other text using the i18n support you should rename and translate `next5Years` to `next12Years` and `prev5Years` to `prev12Years`. You should also add the `backTo` property, which is used for the new *Back to 2016* button when the user enters the Jump Year menu. ## CSS changes Version 3.x uses `em` instead of `px` units. This means that the menu determines it's size according to the `body` element's `font-size`, instead of having a fixed width of `200px`. If you need to resize the menu, add this rule to your CSS: ``` /* Makes the Month Picker menu 20% bigger. */ .month-picker { font-size: 1.2em; } ``` Version 3.x removes: ``` .month-year-input { width: 60px; } ``` If you still want the plugin to implicitly resize the input fields it's applied to you must add this rule to your own CSS. If you explicitly defined a rule that reverts the effects of this rule, it's no longer necessary and it can be deleted. ## Markup changes If you've applied custom CSS to the Month Picker menu, please note that: The following elements were removed: ```