boolean (@NotNull XmlTag tag) { if (!tag.getLanguage().isKindOf(HTMLLanguage.INSTANCE)) return false; XmlDocument doc = PsiTreeUtil.getParentOfType(tag, XmlDocument.class); String doctype = null; if (doc != null) { doctype = XmlUtil.getDtdUri(doc); } doctype = doctype == null ? ExternalResourceManagerEx.getInstanceEx().getDefaultHtmlDoctype(tag.getProject()) : doctype; return XmlUtil.XHTML4_SCHEMA_LOCATION.equals(doctype) || !StringUtil.containsIgnoreCase(doctype, "xhtml"); }