do not logout of server errors 500 or timeouts

src/views/tinode-web.jsx

@@ -724,20 +724,23 @@ class TinodeWeb extends React.Component {
         this.handleLoginSuccessful();
       }
     }).catch(err => {
+      const autoLogin = err.code >= 500;
       // Connection or login failed, report error.
       this.setState({
         loginDisabled: false,
         credMethod: undefined,
         credCode: undefined,
         loadSpinnerVisible: false,
-        autoLogin: false
+        autoLogin: autoLogin
       });
       this.handleError(err.message, 'err');
       console.warn("Login failed", err);
-      if (token) {
-        this.handleLogout();
+      if (!autoLogin) {
+        if (token) {
+          this.handleLogout();
+        }
+        HashNavigation.navigateTo('');
       }
-      HashNavigation.navigateTo('');
     });
   }
 

umd/index.dev.js

@@ -8357,19 +8357,22 @@ class TinodeWeb extends (react__WEBPACK_IMPORTED_MODULE_0___default().Component)
         this.handleLoginSuccessful();
       }
     }).catch(err => {
+      const autoLogin = err.code >= 500;
       this.setState({
         loginDisabled: false,
         credMethod: undefined,
         credCode: undefined,
         loadSpinnerVisible: false,
-        autoLogin: false
+        autoLogin: autoLogin
       });
       this.handleError(err.message, 'err');
       console.warn("Login failed", err);
-      if (token) {
-        this.handleLogout();
+      if (!autoLogin) {
+        if (token) {
+          this.handleLogout();
+        }
+        _lib_navigation_js__WEBPACK_IMPORTED_MODULE_18__["default"].navigateTo('');
       }
-      _lib_navigation_js__WEBPACK_IMPORTED_MODULE_18__["default"].navigateTo('');
     });
   }
   static navigateToCredentialsView(params) {