The Financial Times reports that ISIS has published an Arabic-language manual telling followers that metadata on tweets and other information posted online is allowing western forces to locate them.
A number of security gaps have appeared that have benefited the enemy and have helped expose the identities of some brothers or identify some sites used by the mujahideen with ease … We know this issue is not only tied to pictures, but to PDF files, word files and video files
It is also asking followers not to tweet locations, names, or recognizable photos. Internet cafe owner:
A few stayed online, but no one posts selfies next to chopped-off heads any more