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This is documentation about a configuration directive, which can be placed within Movable Type’s core configuration file, mt-config.cgi, to customize the behavior of the system.

Specifies Movable Type version compatibility for plugin use. Setting to an older version maintains compatibility with older plugins, but with a performance cost.

Allowed Values

  • 0 (compatible with all versions)
  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • etc.




Consider a plugin written based on Movable Type 3. The API used in that version becomes deprecated in version 4 and higher, so if RequiredCompatibility were set to 4, the plugin would not work since the API could not load correctly. In this situation, you would need to use a value of 3 or lower:

RequiredCompatibility 3

On the other hand, if the plugin in question does not rely on any API, the RequiredCompatibility value could be set to 5 or higher, allowing the plugin to work faster.

RequiredCompatibility 6