I recommend using prettyContext.setCurrentConfig(PrettyConfig config) if you really want to change things around at runtime. Note, however, that PrettyContext requires an active HTTPSession in order to get a handle; however, if that is unappealing, you could also use this approach:
servletContext.getAttribute(PrettyContext.CONFIG_KEY) – as long as PrettyFaces has started up, the config should be set in that location. This is not really recommended, however, since it might cause threading issues when modifying the PrettyConfig during web-requests.
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