If we release a Gallery 2.2.2, the following changes should be considered to be included.
Not fixed yet.
Fix core upgrade notification in template
An incorrect variable name (which, sadly we don't get a warning for from Smarty) causes us to fail to see the notification that there's a newer version of the core available. And a quick review of the text shows that one of the bullet points is confusing/unhelpful so I removed it.
Fix for bug 1693956. The core.DownloadItem RewriteRule had a wrong rewrite target URL, it included the sessionId from configuration time. This could well break an embedded G2.2 (losing the session, not seeing non-public content, etc).
Fix for bug 1695294. Need stronger warning when uninstalling plugins.
Fix for bug 1708282. Need stronger warning when deleting plugins if the plugin is installed.
Fix for bug 1593803. Session data could be truncated on large imports from g1 with lots of data.