Click-To-Play Plugin Telemetry

Last week we finally turned on click-to-play plugins as the default state for all plugins except Flash in Nightly builds (which will be Firefox 26). This is a milestone in giving Firefox users control over plugins and helping protect them from being exploited via unused and unwanted plugins.

As part of this feature, we have started to measure how users interact with the click-to-play UI. Nightly users aren’t typical, so this data probably doesn’t mean much yet, but it’s nice to see it in action:


This data shows how many different kinds of plugins were present in the plugin notification UI when each user saw it. When designing the notification, we wanted to streamline the common case, which we believed was that normally there would be only one kind of plugin on a page. This telemetry data will help verify our assumption. The current Nightly data shows a single type of plugin is the most common case, but not by as much as I originally thought:

# of Plugins

Notification Count









5 or more



This data shows what user action triggered showing the plugin notification.

User Action

Notification Count

Click on in-content plugin UI


Click on location bar icon


I’m surprised that so many users are clicking on the location bar icon. That may just be inquisitive users checking what each button does, but I’ll be monitoring this as it goes up the trains to the more representative beta population. If this stays very high, then we may have a problem with distracting users with unnecessary UI.


This data shows what action users are choosing to take in the plugin notification. Note that when multiple plugins are shown in the same notification, there will be a separate action for each plugin:

User Action

Notification Count

Allow Now


Allow Always




I’m a little surprised at the distribution of “Allow Now” and “Allow Always”. When designing this UI, we expected that most users would want the “Allow Always” option, and we wanted to highlight that. But again, Nightly users are atypical and may not be a good sample. I’ll be watching this data also in beta.

I’m a wary of drawing any significant conclusions from early data, but I’m happy that we appear to be collecting the correct data and with the new telemetry dashboard it’s not hard to get at simple measurements such as this. Kudos to Taras, Mark Reid, and Chris Lonnen for getting that runing and the small daily improvements that make all our lives better.

Atom Feed for Comments 14 Responses to “Click-To-Play Plugin Telemetry”

  1. Stephan Sokolow Says:

    In case it helps to have specific details on one skilled user, I tried turning it on explicitly in Aurora 24 and, while I like Firefox’s idea in principle and it’s definitely more eye-pleasing, I went back to NoScript’s plugin blocking for two reasons:

    1. The built-in solution kept interpreting “Allow Now” as “allow anything from this domain for the rest of the session” which caused middle-clicked YouTube videos to start playing unexpectedly. NoScript better supports the “allow just this specific widget for the rest of the session” workflow. (By checking the “Apply these restrictions to whitelisted sites too” checkbox in the Embeddings tab.)

    2. It popped up the “now or always?” pane when I clicked on a widget, forcing me to bring Fitts’s law into play again and click a second time. NoScript lets me “click to play” a widget with a single click, just like the classic (albeit insecure) extensions like Flashblock and the built-in “click to play” offerings in browsers like Chrome and Konqueror.

  2. Honda Says:

    Thanks for posting. Just a quick comment on the “Allow Now” option which is the one i almost use exclusively. The reason is that the plugin content is typically a mediaplayer with autostart enabled, and I really dislike a bunch of videos starting in background tabs (or even in current tab) before I want to watch the content. This scenario is also obvious when a user, like me, uses “show tabs from last time” session option.

  3. Archaeopteryx Says:

    Is there a difference in behavior between e.g. Windows 7 and Windows XP users? For XP people, it’s unexpected that the doorhanger dropdown acts as a button. Furthermore, do you a breakdown of which plugins get enabled and maybe also the dimensions of the plugin area (i.e. if it’s the main or important content on a page and not just a banner)? Thank you in advance.

  4. Bryan Quigley Says:

    I think it would also be useful to collect which plugins are most often “Allowed Once”, “Allowed Always”, or “blocked”. This will help determine which plugins are actually important to a webpage and inform the bigger community which plugins are likely no longer useful.

    Also, the links to the telemetry doesn’t work for me.

  5. Benjamin Smedberg Says:

    Archaeopteryx, there isn’t intended to be a difference in UI between Win7 and WinXP. I’m not sure what you mean by “the doorhanger dropdown acts as a button” but if you think there is a bug, please feel free to file it and I’ll help figure out what’s going on.

    For privacy/footprinting reasons, we have made it a policy not to collect information about which plugins a user has installed or is actually using within telemetry.

    We certainly considered recording plugin dimensions, but there are some technical challenges which make that a bit hard, plus without distinguishing which it is, it’s hard to use the data.

  6. tom jones Says:

    i must voice similar opinions as the first two comments..

    i have click-to-play enabled for all plugins, and this new UX is actually much worse then the one used until the previous beta (i believe).

    i _never_ wish to enable automatic loading of plugins (flash), both because of media autoplay in background tabs, and security reasons (the only security measure i employ in the browser).

    the new UX not only requires more clicks than it should (and than the name would imply), and the second click target is not only small and far away (Fitts’), it also _CHANGES_PLACES_ (between the left “Allow Now” and right “Continue Allowing” button in the doorhanger panel), depending on whether i already clicked “allow” for this particular site (youtube) in this particular browsing session (who cares/remembers).

    it is a UI that is literally un-learnable, as it forces me to read before clicking every single time.

    i understand that me not wanting to load any plugins by default already puts me in the minority, but i still think this use-case should be addressed..

  7. Ferdinand Says:

    Click to play is just a good feature which is why most browsers have it. I have no clue for who this ‘feature’ is. You forced me to install flashblock again. Weird weird choice.

  8. av Says:

    i’m with tom jones, the new UI requires two click even for in-content. However I agree with limiting everything but the latest flash player.

  9. Lozzy Says:

    I’m with Honda in using ‘Allow Now’ almost exclusively. I like to take control of plugin content as far as reasonably possible, so when I prefer only allowing sites plugin privilege when necessary. So I would also prefer that clicking a plugin box immediately enable that item rather than needing a second click on the doorhanger.

    Perhaps it’s a mistake to assume that people would automatically use the ‘Allow Always’ button. Doing so tends to presume that people would be content with less granular control.

  10. Dan Says:

    Like previous commenters I usually use “Allow Now”, though I have permanently allowed two sites (Youtube and a national online TV website). I don’t trust other sites, and they frequently make my browser come to a standstill (I’m using an old computer).

  11. Merike Says:

    One of the reasons to click on location bar icon is when the plugin doesn’t have dimensions or is tiny. For example my bank uses 1x1px object element for Estonian ID-card plugin. There is no visible click-to-play icon on the page.

  12. skierpage Says:

    Can the browser *user* find out how many times a plug-in is activated? My friends’ machines inevitably have Silverlight, Java, random Microsoft media, etc. plug-ins installed; they have no idea if they need those plug-ins or not and I can’t hang around for a few days to see if disabling a plug-in will cause them problems. It would be nice if about:addons showed “Used infrequently (8 times in last year, last on 2013-04-08)”

  13. Oliver Henshaw Says:

    “I’m surprised that so many users are clicking on the location bar icon.”
    I’m not using the nightly, but I have click-to-play for flash and find some sites don’t have any in-content UI to click on. e.g. where the player area is covered by a spinning turntable and I have to use the location bar icon to activate flash. Maybe these users have similar issues?

  14. Steven Says:

    Thanks for finally showing us some numbers on CTP usage. Crippling CTP has been one of the most contentious decisions in the history of Firefox. I am glad we are finally getting some sense back into the discussion. So far we see that people prefer in-content-ui and are very reluctant to allow plugins to auto-play. I am looking forward to seeing those numbers for the beta community. By all means please post them! It might also be interesting to see how many people are going to install the click-to-play-per-element add-on in order to restore true CTP.