Editing Gecko (software) (section)

==Standards support==
{{Update section|date=August 2022}}
Some of the standards Gecko supports include:

* [[CSS]] Level 3
* [[Document Object Model|DOM]]
* [[HTML5]]
* [[JavaScript]] ([[ECMAScript]] ES6 or superior,<ref>{{Cite web |title=Cross Browser Compatibility of ECMAScript 2015 (ES6) in Firefox 102 |url=https://www.lambdatest.com/web-technologies/es6-support-on-firefox-102 |access-date=2022-08-21 |website=www.lambdatest.com |language=en-US |archive-date=2022-08-21 |archive-url=https://web.archive.org/web/20220821071847/https://www.lambdatest.com/web-technologies/es6-support-on-firefox-102 |url-status=dead }}</ref> currently [[ECMAScript]] 2021 ES12), implemented in [[SpiderMonkey]]
* [[MathML]]
* [[Resource Description Framework|RDF]]
* [[XForms]] (via an official extension)
* [[XHTML]] 1.0
* [[XML]] 1.0
* [[XSLT]] and [[XPath]], implemented in TransforMiiX
* [[SVG]]<ref>{{Cite web |title=Cross Browser Compatibility of SVG (basic support) in Firefox 102 |url=https://www.lambdatest.com/web-technologies/svg-support-on-firefox-102 |archive-url=https://web.archive.org/web/20221209094958/https://www.lambdatest.com/web-technologies/svg-support-on-firefox-102 |url-status=dead |archive-date=December 9, 2022 |access-date=2022-08-21 |website=www.lambdatest.com |language=en-US }}</ref>