Here are the main points to WordPress 4.9
- Drafting and scheduling of changes in the Customizer.
- Once you save or schedule a change, when any user comes into the Customizer the pending changes will be autoloaded.
- A button is provided to discard changes to restore the Customizer to the last published state.
- Addition of a frontend preview link to the Customizer, for non-logged in users.
- Addition of autosave revisions in the Customizer
- A brand new theme browsing experience in the Customizer
- Improve the flow for creating new menus in the Customizer
- Support for videos from providers other than YouTube and Vimeo in the Video widget
- Media: Make captions responsive
- Media: fix header crops in Customizer
- Media: Store video creation date in meta
- NEW Gallery widget
- Support for shortcodes in Text widgets
- Support for adding media to Text widgets
- Addition of dirty state for widgets on the Administration Screen, indicating when a widget has been successfully saved and showing an “Are you sure?” dialog when attempting to leave without saving changes