Mozilla has added an experimental feature to the Firefox Nightly edition browser that lets users control if a site is allowed to autoplay sound when it loads. The feature works by showing a popup notification from the left side of the URL address bar. Firefox is now the third major browser after Chrome and Edge that has added a feature to block sites that autoplay. The stable version of Firefox 63 is expected to launch at the end of October, with the feature expected to arrive later this year. The default option is “Always Ask
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