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System and Local Extensions¶
The files for an extension are located in a folder named by the
extension key. The location of this folder can be either inside
The extension must be programmed so that it does automatically detect where it is located and can work from both locations.
Local extensions are located in the
This is where to put extensions which are local for a particular
TYPO3 installation. The
typo3conf directory is always local, containing
local configuration (e.g.
LocalConfiguration.php), local modules etc.
If you put an extension here it will be available for a single TYPO3
installation only. This is a "per-database" way to install an
System extensions are located in the
This is system default extensions which cannot and should not be updated by the EM. They are distributed with TYPO3 core source code and generally understood to be a part of the core system.
Local extensions take precedence which means that if an extension
exists both in
typo3/sysext/ the one in
is loaded. This means that extensions are loaded in the
order of priority local-system.