yarn upgrade

and pin types as per https://github.com/matrix-org/matrix-react-sdk/pull/6813

package.json

@@ -65,8 +65,8 @@
     "matrix-react-sdk": "github:matrix-org/matrix-react-sdk#develop",
     "matrix-widget-api": "^0.1.0-beta.16",
     "prop-types": "^15.7.2",
-    "react": "^17.0.2",
-    "react-dom": "^17.0.2",
+    "react": "17.0.2",
+    "react-dom": "17.0.2",
     "sanitize-html": "^2.3.2",
     "ua-parser-js": "^0.7.24"
   },
@@ -93,8 +93,8 @@
     "@types/flux": "^3.1.9",
     "@types/modernizr": "^3.5.3",
     "@types/node": "^14.14.22",
-    "@types/react": "^17.0.2",
-    "@types/react-dom": "^17.0.2",
+    "@types/react": "17.0.14",
+    "@types/react-dom": "17.0.9",
     "@types/sanitize-html": "^2.3.1",
     "@typescript-eslint/eslint-plugin": "^4.17.0",
     "@typescript-eslint/parser": "^4.17.0",
@@ -151,13 +151,16 @@
     "stylelint-config-standard": "^20.0.0",
     "stylelint-scss": "^3.18.0",
     "terser-webpack-plugin": "^2.3.8",
-    "typescript": "^4.1.3",
+    "typescript": "4.3.5",
     "webpack": "^4.46.0",
     "webpack-cli": "^3.3.12",
     "webpack-dev-server": "^3.11.2",
     "worker-loader": "^2.0.0",
     "worklet-loader": "^2.0.0"
   },
+  "resolutions": {
+    "@types/react": "17.0.14"
+  },
   "jest": {
     "testEnvironment": "jest-environment-jsdom-sixteen",
     "testMatch": [