Allow copying / duplicating multiple slides
Currently we need to copy slides one by one, which is very tedious.
Justin Cobler commented
This is how you Select the slide or slides you want to copy, and then on the Home tab, click Copy.
To select multiple sequential slides, click the first slide, press Shift, and then click the last slide that you want.
To select multiple non-sequential slides, press Ctrl, and then click each slide that you want.