The setting for "show app load time" shows numbers like: - 280ms for browser - 680ms for settings app - 680ms for settings app remodeled to be just an empty index.html Not sure how the value is computed but I believe it should be different at least for the last two cases unless it measures time before any content of the HTML is accessed.

the number is actually right. The issue here is that Settings app is loaded during boot time (bug 808919). It shows the firstpaint. I'd probably prefer to have it show when "localized" is fired (as this is the time when the app is "loaded"), but firstPaint is good enough for now.