See also bug 790765 . The mozbase tests as to be run via `make check` must be very robust and should be disabled if anything goes wrong (with the thought to be reenabled later once issues regarding robustness are resolved; obviously if there is a legitimate issue found by the tests, they shouldn't be disabled but instead addressed). However, developers of mozbase should have a way of running e.g. intermittent tests or tests that otherwise are not robust enough for production automation. One way would be to have two master manifests: one for production and one for development. The upside to this approach is ... ZERO CODE CHANGE! The downside is that both manifests will need to be kept up to date. Depending on what folk desired, it may (or may not) be desirable to improve the manifestdestiny code and/or test.py to this end. This is a spec bug; we should figure out what we want to do first. If the two manifest solution == that, easy enough.