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When however on only 1 side outside of the view period a value is found the time series WILL be considered empty becasue this will not result in drawing a line anyway.
Empty time series hidden via this functionality will still appear in the Visibility Dialog, this is because this dialog is designed to be as complete as possible to keep colors and labels consistent since they depend on the unicity of the time series.
History popup
When clicking ctrl+H on a value, a popup will appear which shows the history of data on that time step.
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