Flash Control


Flash Control v2.1.3: Installing on Cyberfox 43.0.4

Although Flash Control doesn't offer support for Cyberfox, I tested it out on Cyberfox regardless


Flash Control v2.1.0: Test Cases

While I'm perfectly fine with people leaving bug reports here (that's not to say other developers are the same), due to bad experiences with some users, I'm no longer responding to any of the public "reviews" here, good or bad, regardless. I'm sorry about that. If any of you need to contact me for support, come on, you all know how.


It gives you control over which sites are allowed to display the Flash player or the HTML5 player. Flash player plays Flash media (embed/object elements). HTML5 player plays HTML5 media (video/audio elements). Media Source Extensions for HTML5 players are only partially supported. It was originally designed with Youtube in mind.

In addition to the context menu for whitelisting domains, there's also a simple UI, which is accessible via the Sidebar for managing the whitelist.

Q & A:
Q1: It doesn't work on Grooveshark.
  (a) It does work on Grooveshark. You can either click on the toolbar icon to toggle the rule on and off, or manage your whitelist from the Sidebar.
  (b) Update: Grooveshark has shut down its operation.

Q2: The toolbar icon is backwards.
A2: The toolbar icon is NOT backwards. RED means you're "vulnerable"; GREEN means you're safe, ie you don't have to worry about Flash/HTML5 media meddling with your browser. RED is also the color used by Adobe Flash, so when you see the "Adobe Flash" icon, it means it's active. There's nothing to fix in that regards, it's part of the design.

Q3: On youtube, when you switch to a user's homepage, any video there starts automatically.
A3: No, it doesn't.

Q4: I've also noticed on other websites it seems to consider the source of the video more than the current website.I've switched the symbol from red to green with no tangible difference.
A4: Not exactly, only if it utilizes iframe. Believe it or not, that is a design feature, NOT a bug. iframe has its own url. To set the rules for "external" sources, simply right click on the "play icon" ON THE WEBPAGE, and select [Allow "xxx.com"] from the context menu.

Q5: This extension doesn't work well on yahoo.
  (a) Yes. That's true. The play button won't work on yahoo. Yahoo uses javascript to control its Flash player. The only option here is block or unblock.
  (b) Update: From v1.2.3 onwards, it seems like it's working on Yahoo too.

Q6: What do those "play button" icons mean?
A6: "f" represents Flash video; "V" represents HTML5 video; "A" represents HTML5 audio; "V+" represents HTML5 Mediasource video; "A+" represents HTML5 Mediasource audio;

Q7: Why is it that sometimes clicking on the "play button" does seemingly nothing?
A7: Because those are hidden **videos. They generally do nothing.

Q8: Why isn't the "play button" always centered in the middle of the placeholder? Why do I see isolated "play buttons"?
A8: That happens from time to time because:
  (a) The **video doesn't have a dimension.
  (b) The **video has a dimension of less than 48x48 pixels.
  (c) The **video is hidden from the user (either out of the screen or invisible).

Q9: Why is the "play button" so small (only 48px by 48px)?
A9: The plan was to overlay the "play button" on the top layer even for background layers and hidden elements. As such, it has to be small, so that it is as unobtrusive as possible.

Q10: What is the purpose of "Override Ajax Anchor"? I've tried it on and off in youtube and what it does just doesn't seem readily apparent.
  (a) With Youtube, when you click on a hyperlink, you're technically really still on the same page: only the contents within the page and the URL string in the address bar are updated, bypassing the conventional method of retrieving pages on the web. That's the power of AJAX (some called it XHR). With "Override Ajax Anchor" "on", we're reverting to the non-ajax method of retrieving webpages. The default value is "off".
  (b) It's not apparent because starting from v1.2.2, Flash Control has changed its way of handling AJAX "pages" on Youtube, essentially treating them as separate pages. There's a huge distinction in prior versions.

Q11: It doesn't block stuff until I restarted Firefox.
A11: It is in effect right after installation, BUT only on new browser tabs and windows. That my design philosophy, NOT a bug.

Q12: What does Flash Control "block"?
A12: Flash Control blocks Adobe Flash contents from autoplaying. It also blocks HTML5 media from autoplaying. It only has PARTIAL ("best efforts" only) support for Media Source Extensions for HTML5 media.

Q13: Why doesn't Flash Control sidebar display right when AIOS is installed?
A13: That has nothing to do with Flash Control. [details]

Q14: What does "Ignore Flash Plugin State" do, and when do I need it?
  (a) If a user changed the default Firefox settings, ie set the Flash plugin settings to "Ask to Activate", Flash Control's default behavior is to let Firefox handle it, and we are done there. If the user somehow, wanted to manage Flash over 2 UI interfaces: Firefox's very own "Click to Play" and Flash Control, then he has to select "Ignore Flash Plugin State". If the user had stuck with all the default settings, then he doesn't have to change anything here. [details]
  (b) Update: This feature is removed.

Q15: Is it possible to block preloading videos?
(a) It does stop videos from preloading (if we're going by the HTML5 definition). That has been the case since the very FIRST version.
(b) It ALSO stops and prevents videos from loading for Flash and HTML5 elements; please note however that, that does NOT (please pay attention here) include Media Source Extensions for HTML5 elements. [details]

Q16: Does Not Block Html5 On Twitch.tv
A16: Please find me a HTML5 video link on twitch.tv (September 15, 2015).

Q17: With 2.0.4, I now have an annoying HTML5 audio icon shown in site xyz.com. There is no flash, audio or html5 present.
A17: Starting from 2.0.4, Flash Control also blocks HTML5 audios that are not in the DOM, ie those audio nodes are not attached to the document. [details]

**video denotes flash elements or HTML5 video/audio elements

Please note that the Mozilla forums is not tied to your AMO account, so you might need to register a new user id in order to use the forums.

Developer's Note:
1. The UI for the whitelist was made available since v1.0.9.
2. Blocking engine was changed from polling to event listeners since v1.1.8.
3. "Play button" was implemented as an overlay since v1.2.2.
4. Flash Control activates at page-start instead of page-ready since v1.2.3.
5. HTML5 audio nodes that were not attached to the DOM are also blocked starting from v2.0.4.
6. Persistent storage changed from IndexedDB to SQLite since v2.0.9.
7. For "bug reports", please provide the exact URL.
8. Please do not report those older "reviews" even if they sounded wrong. I'm only interested in the current version, because if I'd missed anything, I'm sure I would be reminded again.

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