Click-to-play plug-ins gives you the chance to stop video plug-ins from starting as soon as you load a web page, but so many websites are switching to HTML5 video and it is still possible to stop autoplay in many browsers.
What will have below will also stop HTML5 audio from automatically playing. Any websites that use the <audio> and <video> tags to play back multimedia will be affected. Unfortunately, only some web browsers allow you to do this.
The Videos Will Still Buffer
Stoping automatic playback just pauses the video; it doesn’t stop it from loading. How the video is set to load depends on the page, your browser may automatically download the entire video or just begin buffering part of it, even if you haven’t loaded it yet. This won’t prevent media from downloading entirely, as click-to-play did for Flash content.
In other words, if you’d like to use this trick to save bandwidth, it won’t help much.
Firefox contains a preference that lets you disable whether HTML5 videos on web pages automatically play or not. However, like many Firefox preferences, this one is buried deep in about:config where you’d otherwise never find it.
Mozilla improved this preference in Firefox 41, gives it more power. When you stop autoplay of HTML5 media, scripts running on the current web page won’t be able to start media unless you gives it access to do that. A script running in the background can’t just instruct the video to play without your permission.
To stop this autoplay, plug about:config into Firefox’s address bar and press Enter. Agree to the warning and then type “autoplay” into the search box. You’ll see a preference named “media.autoplay.enabled”, which will be set to True. Double-click that preference and it will change to False.
This feature doesn’t come with Chrome but it is possible to stop many HTML5 videos on the web from automatically playing by installing the Stop YouTube HTML5 AutoPlay browser extension from the Chrome Web Store. Despite its name, this should work with all websites — not just YouTube. Here’s the developer’s website.
If this extension doesn’t work, you may need to try the Disable HTML5 Autoplay extension.
This one has few users, but it disable autoplay in all situations — including blocking scripts from automatically playing videos and parsing new HTML5 videos as they’re dynamically loaded on web pages. Of course, this same add-on will also work in Chromium.
Opera is just like Google Chrome, and supports the same browser extensions. The same Disable HTML5 Autoplay extension you can use on Chrome is also available for Opera.
It doesn’t seem possible to do this on Apple’s Safari web browser. Safari has no built-in preference you can use to stop this, and there are no browser extensions like the ones available for Chrome and Chromium-based web browsers to stop this action from taking place. A browser extension could theoretically add this feature to Safari, if someone were to create one.
You can’t prevent this on Microsoft Edge because it is not built into the browser, so it’s just not possible. Microsoft’s new Edge browser doesn’t yet support add-ons, so there’s no way to install a third-party extension to have this feature. It will probably be possible with a similar browser extension to the one Chrome uses after Edge gains support for these.
This is not possible in Internet Explorer, either. Internet Explorer doesn’t have this option built in, and it doesn’t seem like there’s any browser add-on that does this. This isn’t surprising, as browser extensions have always been the big way Microsoft’s web browser is behind its competitors.