An <outline> element whose type is "rss" may have a version attribute, whose value must be RSS, RSS1, RSS2, or scriptingNews.
From the OMPL guidelines: version varies depending on the version of RSS that's being supplied. It was invented at a time when we thought there might be some processors that only handled certain versions, but that hasn't turned out to be a major issue. The values it can have are: RSS1 for RSS 1.0; RSS for 0.91, 0.92 or 2.0; scriptingNews for scriptingNews format.
Either omit the version attribute entirely, or change it to be one of values listed above.
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