Currently in Nightly (05/06) when one attempts to install any fashioned (hosted or packaged, thus far tried) Web Application, the client will display multiple installation prompts. As well, on successful install one will also bare witness to multiple context-menu prompts on attempt to long-press on the installed application in about:apps. Steps to Reproduce: i) http://testmanifest.com/ or head to Firefox Marketplace and install 'Twitter' Expected Results: Single installation prompt. Actual Results: Multiple installation prompts. i) On successful installation, visit about:apps in the browser ii) Long-tap on recently installed web application Expected Results: Single context-menu prompt. Actual Results: Multiple context-menu prompts.
Re-created my profile and this now works for me. Will re-open if I see this in the future.