As you can read on the Joomla website, the security update V2.5.28 is the last planned update available for Joomla 2.5 . What does this mean for users who have not yet completed the transition to Joomla 3.x ?
Your websites will keep working as normal, but there are some serious BUTs. End of support means that you no longer get bug fixes, features, or security updates for this release.
If you are planning to upgrade to Joomla! 3 (which you should!) it is necessary to check first whether the previously used server environment is also compatible with Joomla 3. Joomla 2.5 worked with the combination of PHP 5.2.4 / MySQL 5.0.4. The the minimum requirement for Joomla v3.x is nowPHP 5.3.10 / MySQL 5.1.0.
More Information: joomla.com
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