boolean (final XmlTag tag) { String tagName = tag.getName(); if (tag instanceof HtmlTag) tagName = StringUtil.toLowerCase(tagName); Language language = tag.getLanguage(); return ourTagsWithEmptyEndsNotAllowed.contains(tagName) && (language.isKindOf(HTMLLanguage.INSTANCE) || language.isKindOf(XHTMLLanguage.INSTANCE)) || (language.isKindOf(HTMLLanguage.INSTANCE) && !HtmlUtil.isSingleHtmlTag(tag, false) && tagName.indexOf(':') == -1 && !XmlExtension.isCollapsible(tag)); }