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In Struts 2 Dojo is configured with a small dojo.js file that load other javascript resources only as required. Slow page-loads can be experienced when using the Struts 2 ajax theme as Dojo sequentially issues the series of resource requests. Performance may be significantly improved by creating a custom Dojo profile that bundles more resources directly into dojo.js.
Creating a custom Dojo profile for Struts 2.0.9x
More Struts 1 -> 2 migration tips
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