Version 4.6 is a major WordPress release, so you’ll have to update it manually. But don’t forget to back-up first.
A couple of things that immediately strike you are the slicker installation process of plugins and updates for themes, it is quicker and more intuitive.
Highlighting Broken Links in Visual Editor
Sometimes users end up adding a broken link or improper URL in a post. If you publish the post, then that misspelled link goes live too.
WordPress will now attempt to check for broken or poorly formatted links when you are using the visual editor. If a link is broken, then it will highlight the linked anchor text with red dots, showing the link URL in red.
Autosave and Recovery fine-tuned
WordPress 4.6 comes with a better disaster recovery mode for the auto-save feature in the post editor. Previously, when users disabled revisions, it affected restoring drafts from browser cache and autosave feature.
This issue is now fixed and users will be able to easily restore posts from browser backups and autosave.
Introducing WordPress 4.6: