Unicode and HTML with detectable errors. Currently, Gecko browsers such as Firefox, abide to this rule, whereas the bulk of the other common browsers that support HTML as XML, such as Webkit browsers (Chrome/Safari) do allow the encoding of XHTML documents to be manually overridden. Many browsers are only capable of displaying a small subset of the full Unicode repertoire. Here is how your browser displays various Unicode code points: Some web browsers, such as Mozilla Firefox, Opera, Safari and Internet Explorer (from version 7 on), are able to display multilingual web pages by intelligently choosing a font to display each individual character
Adobe Flash enable this option permanently. Both Chrome and Firefox have an option to enable "click to play plugins". Equivalent "Flash blocker" extensions are also available for many popular browsers: Firefox has Flashblock and NoScript, Internet Explorer has Foxie, which contains a number of features, one of them named Flashblock. WebKit-based browsers under macOS, such as Apple's Safari, have ClickToFlash. Firefox (from version 46) rewrites old Flash-only YouTube embed code into YouTube's modern embedded player that is capable of using either HTML5 or Flash. Such embed code is used by non-YouTube sites to embed YouTube's videos, and can still be encountered, for