To display the onboarding flow, we need to decide if a given profile corresponds to an existing devtools user or not. Existing devtools users should skip the onboarding flow and directly open devtools. For the short term we will reuse existing prefs to guess if the user is an active devtools user or not (see Bug 1408337) We could design a preference that measures the user's interaction with DevTools and decays as time passes (something along the lines of https://www.chromium.org/developers/design-documents/site-engagement). This would allow us to identify devtools users from non devtools users but could also give us more fine grained information to push content to our users.
Here my shot for an MVP engagement pref based on Chrome's site-engagement - Engagement score is a number from 0-100 - Activity increases score, by a maximum of 25 per browser session - Opening devtools increased the score by 1 - Switching panels increases the score by 1 - Refresh or page navigation with panel open increases the score by 1 - Startup decays the score by 5 This first shot does not seem too complicated, but I'd like feedback on the general idea. I have not done much math to map it against different user types (2d/week, 1d/week, daily user); which should be interesting as validation.