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Current and the previous two minor releases will receive active security updates by the core development team. As of April 202022020, that means the 2.4.x, 2.3.x releases are maintained by the core development team. Releases outside of this window will be patched on a case-by-case basis depending on several factors, including: ease of development/testing of a patch for the version, compatibility of a patch for a supported release being applied to an unsupported release, and community contributions of patches for a targeted unsupported version.
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