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When generating within the top level, content will be generated into the target/site location of the subproject, then copied into the right place within the target/site of the top level project, using the difference between the top level URL and the subproject's URL as the relative path to use (which will default to artifactId). It will not be possible to navigate between the sites on the filesystem - you must push to staging to achieve this.

When generated within the subproject, it is only generated into the subproject. The site will appear correctly, but navigating to upper levels will not be possible when previewing. However, it can be deployed from there directly into the right subdirectory on the site.

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