diff --git a/package.json b/package.json
index d688f1e5d..8d352eedd 100644
--- a/package.json
+++ b/package.json
@@ -118,7 +118,7 @@
     "stylelint-webpack-plugin": "1.1.2",
     "supertest": "4.0.2",
     "typeface-roboto": "0.0.75",
-    "typescript": "3.7.4",
+    "typescript": "3.9.6",
     "uglifyjs-webpack-plugin": "2.2.0",
     "url-loader": "3.0.0",
     "validator": "12.1.0",
@@ -169,7 +169,6 @@
   "scripts": {
     "type-check": "tsc --noEmit --pretty",
     "type-check:watch": "npm run type-check -- --watch",
-    "type-check-strict:watch": "tsc --project ./tsconfig.strict.json --noEmit --pretty --watch",
     "release": "standard-version -a",
     "test:clean": "npx jest --clearCache",
     "test:acceptance": "codeceptjs run --steps",
diff --git a/src/App/Header/Header.tsx b/src/App/Header/Header.tsx
index 30045c926..8e6664b2e 100644
--- a/src/App/Header/Header.tsx
+++ b/src/App/Header/Header.tsx
@@ -22,9 +22,9 @@ interface Props {
 const Header: React.FC<Props> = ({ withoutSearch }) => {
   const { t } = useTranslation();
   const appContext = useContext(AppContext);
-  const [isInfoDialogOpen, setOpenInfoDialog] = useState();
-  const [showMobileNavBar, setShowMobileNavBar] = useState();
-  const [showLoginModal, setShowLoginModal] = useState(false);
+  const [isInfoDialogOpen, setOpenInfoDialog] = useState<boolean>(false);
+  const [showMobileNavBar, setShowMobileNavBar] = useState<boolean>(false);
+  const [showLoginModal, setShowLoginModal] = useState<boolean>(false);
 
   if (!appContext) {
     throw Error(t('app-context-not-correct-used'));
diff --git a/src/App/Header/HeaderRight.tsx b/src/App/Header/HeaderRight.tsx
index ece4ff643..3265b344a 100644
--- a/src/App/Header/HeaderRight.tsx
+++ b/src/App/Header/HeaderRight.tsx
@@ -27,8 +27,8 @@ const HeaderRight: React.FC<Props> = ({
   onOpenRegistryInfoDialog,
 }) => {
   const themeContext = useContext(ThemeContext);
-  const [anchorEl, setAnchorEl] = useState();
-  const [isMenuOpen, setIsMenuOpen] = useState();
+  const [anchorEl, setAnchorEl] = useState<HTMLElement | null>(null);
+  const [isMenuOpen, setIsMenuOpen] = useState<boolean>(false);
 
   const { t } = useTranslation();
 
diff --git a/src/App/Header/LoginDialog/LoginDialog.tsx b/src/App/Header/LoginDialog/LoginDialog.tsx
index bf6916aee..4b78ee060 100644
--- a/src/App/Header/LoginDialog/LoginDialog.tsx
+++ b/src/App/Header/LoginDialog/LoginDialog.tsx
@@ -3,7 +3,7 @@ import { useTranslation } from 'react-i18next';
 
 import Dialog from 'verdaccio-ui/components/Dialog';
 import DialogContent from 'verdaccio-ui/components/DialogContent';
-import { makeLogin } from 'verdaccio-ui/utils/login';
+import { makeLogin, LoginError } from 'verdaccio-ui/utils/login';
 import storage from 'verdaccio-ui/utils/storage';
 
 import AppContext from '../../../App/AppContext';
@@ -25,7 +25,7 @@ const LoginDialog: React.FC<Props> = ({ onClose, open = false }) => {
     throw Error(t('app-context-not-correct-used'));
   }
 
-  const [error, setError] = useState();
+  const [error, setError] = useState<LoginError>();
 
   const handleDoLogin = useCallback(
     async (data: FormValues) => {
diff --git a/src/pages/Version/VersionContextProvider.tsx b/src/pages/Version/VersionContextProvider.tsx
index 8ec31066d..755ef2f75 100644
--- a/src/pages/Version/VersionContextProvider.tsx
+++ b/src/pages/Version/VersionContextProvider.tsx
@@ -1,5 +1,6 @@
 import React, { useEffect, useState } from 'react';
 import { useParams } from 'react-router-dom';
+import { PackageMetaInterface } from 'types/packageMeta';
 
 import { callDetailPage, callReadme } from 'verdaccio-ui/utils/calls';
 
@@ -17,10 +18,10 @@ const VersionContextProvider: React.FC = ({ children }) => {
   const { version, package: pkgName, scope } = useParams<Params>();
   const [packageName, setPackageName] = useState(getRouterPackageName(pkgName, scope));
   const [packageVersion, setPackageVersion] = useState(version);
-  const [packageMeta, setPackageMeta] = useState();
-  const [readMe, setReadme] = useState();
-  const [isLoading, setIsLoading] = useState(true);
-  const [hasNotBeenFound, setHasNotBeenFound] = useState();
+  const [packageMeta, setPackageMeta] = useState<PackageMetaInterface>();
+  const [readMe, setReadme] = useState<string>();
+  const [isLoading, setIsLoading] = useState<boolean>(true);
+  const [hasNotBeenFound, setHasNotBeenFound] = useState<boolean>();
 
   useEffect(() => {
     const updatedPackageName = getRouterPackageName(pkgName, scope);
diff --git a/src/utils/api.test.ts b/src/utils/api.test.ts
index 1f5e4d75e..1c9ba8703 100644
--- a/src/utils/api.test.ts
+++ b/src/utils/api.test.ts
@@ -3,16 +3,18 @@ import api, { handleResponseType } from '../../src/utils/api';
 describe('api', () => {
   describe('handleResponseType', () => {
     test('should handle missing Content-Type', async () => {
+      const responseText = `responseText`;
+      const ok = false;
       const response: Response = {
         url: 'http://localhost:8080/-/packages',
-        ok: false,
+        ok,
         headers: new Headers(),
+        text: async () => responseText,
       } as Response;
 
       const handled = await handleResponseType(response);
 
-      // Should this actually return [false, null] ?
-      expect(handled).toBeUndefined();
+      expect(handled).toEqual([ok, responseText]);
     });
 
     test('should test tgz scenario', async () => {
@@ -94,9 +96,9 @@ describe('api', () => {
 
       expect(fetchSpy).toHaveBeenCalledWith('https://verdaccio.tld/resource', {
         credentials: 'same-origin',
-        headers: {
+        headers: new Headers({
           Authorization: 'Bearer token-xx-xx-xx',
-        },
+        }),
         method: 'GET',
       });
       expect(response).toEqual({ c: 3 });
diff --git a/src/utils/api.ts b/src/utils/api.ts
index 255db79b2..21b83d57d 100644
--- a/src/utils/api.ts
+++ b/src/utils/api.ts
@@ -6,7 +6,7 @@ import '../../types';
  * @param {object} response
  * @returns {promise}
  */
-export function handleResponseType(response: Response): Promise<[boolean, Blob | string] | void> {
+export function handleResponseType(response: Response): Promise<[boolean, any]> {
   if (response.headers) {
     const contentType = response.headers.get('Content-Type');
     if (contentType && contentType.includes('application/pdf')) {
@@ -26,7 +26,7 @@ export function handleResponseType(response: Response): Promise<[boolean, Blob |
     }
   }
 
-  return Promise.resolve();
+  return Promise.all([response.ok, response.text()]);
 }
 
 class API {
@@ -36,10 +36,11 @@ class API {
     }
 
     const token = storage.getItem('token');
-    if (token && options.headers && typeof options.headers['Authorization'] === 'undefined') {
-      options.headers = Object.assign({}, options.headers, {
-        ['Authorization']: `Bearer ${token}`,
-      });
+    const headers = new Headers(options.headers);
+
+    if (token && headers.has('Authorization') === false) {
+      headers.set('Authorization', `Bearer ${token}`);
+      options.headers = headers;
     }
 
     if (!['http://', 'https://', '//'].some(prefix => url.startsWith(prefix))) {
diff --git a/src/utils/calls.ts b/src/utils/calls.ts
index fb2bb713a..9a372f45a 100644
--- a/src/utils/calls.ts
+++ b/src/utils/calls.ts
@@ -2,15 +2,15 @@ import { PackageMetaInterface } from '../../types/packageMeta';
 
 import API from './api';
 
-export async function callReadme(packageName: string, packageVersion?: string): Promise<string | {}> {
-  return await API.request<string | {}>(
+export async function callReadme(packageName: string, packageVersion?: string): Promise<string> {
+  return await API.request<string>(
     `package/readme/${packageName}${packageVersion ? `?v=${packageVersion}` : ''}`,
     'GET'
   );
 }
 
-export async function callDetailPage(packageName: string, packageVersion?: string): Promise<PackageMetaInterface | {}> {
-  const packageMeta = await API.request<PackageMetaInterface | {}>(
+export async function callDetailPage(packageName: string, packageVersion?: string): Promise<PackageMetaInterface> {
+  const packageMeta = await API.request<PackageMetaInterface>(
     `sidebar/${packageName}${packageVersion ? `?v=${packageVersion}` : ''}`,
     'GET'
   );
diff --git a/tsconfig.json b/tsconfig.json
index f497a7b38..1b08469bf 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -4,7 +4,6 @@
     "target": "esnext",
     "module": "commonjs",
     "moduleResolution": "node",
-    "noImplicitAny": false,
     "strict": true,
     "outDir": "build",
     "allowSyntheticDefaultImports": true,
diff --git a/tsconfig.strict.json b/tsconfig.strict.json
deleted file mode 100644
index 69bad499a..000000000
--- a/tsconfig.strict.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-    "extends": "./tsconfig.json",
-    "compilerOptions": {
-        "noImplicitAny": true
-    }
-}
\ No newline at end of file
diff --git a/yarn.lock b/yarn.lock
index d0a526315..e8da54bf9 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -14803,10 +14803,10 @@ typeface-roboto@0.0.75:
   resolved "https://registry.verdaccio.org/typeface-roboto/-/typeface-roboto-0.0.75.tgz#98d5ba35ec234bbc7172374c8297277099cc712b"
   integrity sha512-VrR/IiH00Z1tFP4vDGfwZ1esNqTiDMchBEXYY9kilT6wRGgFoCAlgkEUMHb1E3mB0FsfZhv756IF0+R+SFPfdg==
 
-typescript@3.7.4:
-  version "3.7.4"
-  resolved "https://registry.verdaccio.org/typescript/-/typescript-3.7.4.tgz#1743a5ec5fef6a1fa9f3e4708e33c81c73876c19"
-  integrity sha512-A25xv5XCtarLwXpcDNZzCGvW2D1S3/bACratYBx2sax8PefsFhlYmkQicKHvpYflFS8if4zne5zT5kpJ7pzuvw==
+typescript@3.9.6:
+  version "3.9.6"
+  resolved "https://registry.npmjs.org/typescript/-/typescript-3.9.6.tgz#8f3e0198a34c3ae17091b35571d3afd31999365a"
+  integrity sha512-Pspx3oKAPJtjNwE92YS05HQoY7z2SFyOpHo9MqJor3BXAGNaPUs83CuVp9VISFkSjyRfiTpmKuAYGJB7S7hOxw==
 
 uglify-js@3.4.x:
   version "3.4.10"