FAYETTEVILLE, Ark.—A computer used by Josh Duggar at work contained child pornography behind a partition that allowed the user to circumvent an application that monitors internet use, and metadata indicates the images were downloaded when the former reality TV star was working, computer forensics experts testified. Duggar, 33, is charged with receiving and possessing child pornography and faces up to 20 years in prison on each count if convicted. His federal trial began this week in northwest Arkansas. Defense attorneys for Duggar have argued that someone else downloaded or placed the child pornography onto the work computer, noting that no child pornography was found on Duggar’s phone or laptop. But federal prosecutors have detailed logs showing, minute by minute, the activity on Duggar’s computer that alternated between him sending personal messages, downloading child porn, and saving pictures of notes. On Thursday, Justice Department computer expert James Fottrell testified that a …