In T85736#1129500, @commy2 wrote:

@Xeno

Yeah, I noticed that too. Apparently it's a campaign / set of missions.

https://forums.bistudio.com/topic/186001-sp-campaign-delta-force-altis/raft wars

Installation:
Extract "DFA.pbo" to your "Steam\SteamApps\common\Arma 3\Campaigns" folder.

The developer wrote that this is the way to install it, but I don't think you are supposed to throw any files inside the Campaigns folder (which doesn't even exist, you have to make one), similar to how you are not supposed to put files inside the Addons-folder.

ref: https://forums.bistudio.com/topic/168277-cba-community-base-addons-arma-3/page-31