[folding] regions for html. Fixes #39409

extensions/html/language-configuration.json

@@ -22,5 +22,11 @@
 		{ "open": "[", "close": "]"},
 		{ "open": "(", "close": ")" },
 		{ "open": "<", "close": ">" }
-	]
+	],
+	"folding": {
+		"markers": {
+			"start": "^\\s*<--\\s*#region\\b",
+			"end": "^^\\s*<--\\s*#endregion\\b"
+		}
+	}
 }

extensions/html/package.json

@@ -67,6 +67,16 @@
         }
       }
     ],
+    "folding": {
+      "markers": {
+        "start": "^\\s*<!--\\s*#region\\b\\s*(.*?)-->/",
+        "end": "^\\s*<!--\\s*#endregion\\b\\s*(.*?)-->/"
+      }
+    },
+		"snippets": [{
+			"language": "html",
+			"path": "./snippets/html.snippets.json"
+		}],
     "configuration": {
       "id": "html",
       "order": 20,

extensions/html/snippets/html.snippets.json

@@ -18,5 +18,19 @@
 			"</html>"
 		],
 		"description": "Simple HTML5 starting point"
+	},
+	"Region Start": {
+		"prefix": "#region",
+		"body": [
+			"<!-- #region -->"
+		],
+		"description": "Folding Region Start"
+	},
+	"Region End": {
+		"prefix": "#endregion",
+		"body": [
+			"<!-- #endregion -->"
+		],
+		"description": "Folding Region End"
 	}
-}
+}