We should probably test when `runtime.XPCOMABI` throws a ` NS_ERROR_NOT_AVAILABLE` error too. Actually, we should handle this scenario in `system/runtime` module, because the getter is executed there. See [MDN](https://developer.mozilla.org/en-US/docs/XPCOM_Interface_Reference/nsIXULRuntime) and the [implementation](https://mxr.mozilla.org/mozilla-central/source/toolkit/xre/nsAppRunner.cpp#732).