The Content tab in the Portfolio shows the strategies in the Portfolio. Additionally it allows you to sort, filter, recalculate the strategies and remove any correlated strategies.
Calculate - Recalculate the strategies' backtest and Portfolio statistics for the current set of strategies and data.
Progress - How much of the recalculation work has been done so far.
Download - Download a collection file with the strategies in the portfolio. (If you are looking to export a Portfolio Expert Advisor you can get it on the Summary tab)
Upload - Upload a collection of strategies to the Portfolio.
Remove all - Remove all strategies in the Portfolio
The Portfolio's sorting and filtering features work at the same way as in the Collection.