Cross Posted from: http://blog.cpanel.com/its-time-to-say-goodbye-to-x3/ Over the past year, we've talked prominently about the impending deprecation of X3, the previous generation user interface for cPanel. Today's the day we are officially announcing a deprecation schedule and its eventual removal from the product. Here's the schedule: In 11.52... Brand new installations of cPanel & WHM will consider Paper Lantern to be the default theme for all new accounts. Already existing installations of cPanel & WHM will not be affected. If you are using a third-party theme, you will also not be affected. In 11.54... Non-emergency and non-security related maintenance for X3 will wind down. cPanel's development and release teams will retarget all upcoming development to Paper Lantern only. As a result of updating from any previous version of cPanel & WHM to 11.54, pre-existing accounts and packages/plans which are found to still be using X3 will be updated to use Paper Lantern with the Retro style applied. There are a couple of important exceptions to this rule: Accounts using third-party themes like RVSkins, CleanPanel, or CPSkins will not be migrated to Paper Lantern. Accounts using a forked copy of X3 (a folder within /usr/local/cpanel/base/frontend) will not be migrated to Paper Lantern. Accounts using a customized brand of X3 will not be affected. If you have created a branding package for X3, your accounts will not be migrated. Accounts which are using one of the default styles like "Black Ice", "Blue Lagoon" or "Mobile" shipped with X3 WILL be migrated to Paper Lantern with the Retro Style applied. cPanel and WHM's public documentation for 11.54 will assume the Paper Lantern interface. Public documentation for previous versions of cPanel & WHM will be unaffected. In 11.56... We are intentionally leaving 11.56 empty in the deprecation schedule to accommodate any unforeseen schedule changes as well as customers and third party plugin developers requiring time to perform any manual migrations. In 11.58... X3 will no longer be shipped in cPanel & WHM. Customization features inside WHM which operate only on X3 will be removed. A couple of things you need to keep in mind going forward: X3 will not be removed from pre-existing installations of cPanel & WHM during the update process to 11.58. If you are using a branded X3 interface, you may continue to do so. We will simply be halting all updates to X3. For those of you who have forked X3 and are maintaining your own theme, you will be unaffected by this change. It is the responsibility of third-party developers to update their plugins to run within Paper Lantern. If you think that an important plugin you use is not Paper Lantern ready, please contact its developers and let them know. The legacy LANG system which was deprecated in cPanel & WHM 11.46 will be removed entirely with the removal of X3. If your third party plugin relies on this deprecated localization system, it will begin to error at this point. We will not be releasing X3 in the form of a plugin or any other distribution. Customers who choose to continue to use X3 from previous installations will do so at their own risk. While the Retro Style for Paper Lantern will approximate the appearance of X3, it will not be a perfect implementation. We are providing the Retro Style to ease the transition for users, not as a final destination for users. We may chose to disable new user interface features in the Retro Style rather than forcibly adapt them into this holdover style. A separate deprecation schedule for the Retro Style will be announced in the future. Roughly speaking, this schedule will take about 1 calendar year to complete. We will be updating this schedule from time to time so that everyone will know what can be expected. During this time, all general maintenance and ongoing bug fixes for any previous version of cPanel we have shipped will continue according to our Long Term Support Policy. Once 11.58 reaches 'End of Life' status, X3 will no longer be maintained by cPanel for all versions 11.58 and newer. We realize that large deprecations like this can cause concern and alarm. Please comment below on this blog post, or reach out to your cPanel account manager if you have any questions.