IntelliJ html
The plugin is bundled with IntelliJ IDEA and enabled by default.
IntelliJ IDEA brings powerful support for HTML that includes syntax and error highlighting, formatting according to the code style, structure validation, code completion, on-the-fly preview during a debugging session (Live Edit) or in the dedicated preview tab in the code editor, and much more.
HTML specification is configurable with the Default HTML language level preference on the Languages & Frameworks | Schemas and DTDs page of the IDE settings Ctrl+Alt+S. By default, specification HTML 5.0 from W3C is assumed.
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