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Tapestry 5.4.2 is a drop-in replacement for Tapestry 5.4 releases. To upgrade, just update the dependency in your build configuration (Maven POM, Gradle build script, etc.) – or Release Notes 5.4.2 Download the new JAR file -- and the new version will just work. However, please review the Release Notes 5.4.2 How to Upgrade instructions before upgrading.
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