This plugin adds a message before or after your post content when this post is outdated
Displays a message at the top of single posts published x years ago or earlier, informing about content that may be outdated.
Show a message if the user using a outdated browser.
OSD Outdated Browser widget allows you to display a custom banner for users using old browsers.
Display a notification box on the single view of your outdated posts, given a set amount of time (configurable).
Deprecation Checker simply scans your plugins, themes, and custom directories for deprecated functions.