diff --git a/lib/reducers/sessions.ts b/lib/reducers/sessions.ts
index ade6a2bc..0cdab94a 100644
--- a/lib/reducers/sessions.ts
+++ b/lib/reducers/sessions.ts
@@ -35,7 +35,7 @@ function Session(obj: Immutable.DeepPartial<session>) {
 }
 
 function deleteSession(state: sessionState, uid: string) {
-  return state.updateIn(['sessions'], (sessions: typeof state['sessions']) => {
+  return state.updateIn(['sessions'], (sessions: (typeof state)['sessions']) => {
     const sessions_ = sessions.asMutable();
     delete sessions_[uid];
     return sessions_;
diff --git a/package.json b/package.json
index 47b89fb6..302dba55 100644
--- a/package.json
+++ b/package.json
@@ -128,7 +128,7 @@
     "null-loader": "4.0.1",
     "playwright": "1.30.0",
     "plist": "3.0.6",
-    "prettier": "2.8.1",
+    "prettier": "2.8.4",
     "proxyquire": "2.1.3",
     "redux-devtools-extension": "2.13.9",
     "style-loader": "3.3.1",
diff --git a/yarn.lock b/yarn.lock
index 88396ec0..7f9538b1 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -6654,10 +6654,10 @@ prettier-linter-helpers@^1.0.0:
   dependencies:
     fast-diff "^1.1.2"
 
-prettier@2.8.1:
-  version "2.8.1"
-  resolved "https://registry.npmjs.org/prettier/-/prettier-2.8.1.tgz#4e1fd11c34e2421bc1da9aea9bd8127cd0a35efc"
-  integrity sha512-lqGoSJBQNJidqCHE80vqZJHWHRFoNYsSpP9AjFhlhi9ODCJA541svILes/+/1GM3VaL/abZi7cpFzOpdR9UPKg==
+prettier@2.8.4:
+  version "2.8.4"
+  resolved "https://registry.npmjs.org/prettier/-/prettier-2.8.4.tgz#34dd2595629bfbb79d344ac4a91ff948694463c3"
+  integrity sha512-vIS4Rlc2FNh0BySk3Wkd6xmwxB0FpOndW5fisM5H8hsZSxU2VWVB5CWIkIjWvrHjIhxk2g3bfMKM87zNTrZddw==
 
 pretty-ms@^8.0.0:
   version "8.0.0"