Checked both fedora-bookmarks-15-4.fc20 and fedora-bookmarks-15-5.fc21. No broken links.
Please note the target of the Release Note link is file:///usr/share/doc/fedora-release-notes/index.html, so we have to be sure that in F21 the release notes is in the right place.
When Fedora.Next will be released perhaps we should update links.
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