diff --git a/lib/redux/app/app_middleware.dart b/lib/redux/app/app_middleware.dart
index 5aa390ef4..e4f1d0d72 100644
--- a/lib/redux/app/app_middleware.dart
+++ b/lib/redux/app/app_middleware.dart
@@ -234,10 +234,10 @@ Middleware<AppState> _createLoadState(
       store.dispatch(LoadStateSuccess(appState));
       store.dispatch(RefreshData(
           completer: Completer<Null>()
-            ..future.then<Null>(() {
+            ..future.then<Null>((_) {
               AppBuilder.of(navigatorKey.currentContext!)!.rebuild();
               store.dispatch(UpdatedSetting());
-            } as FutureOr<Null> Function(Null))));
+            })));
 
       if (uiState!.currentRoute != LoginScreen.route &&
           uiState!.currentRoute.isNotEmpty) {
diff --git a/lib/redux/auth/auth_middleware.dart b/lib/redux/auth/auth_middleware.dart
index 99368e47d..d7085c079 100644
--- a/lib/redux/auth/auth_middleware.dart
+++ b/lib/redux/auth/auth_middleware.dart
@@ -379,12 +379,12 @@ Middleware<AppState> _createCompany(AuthRepository repository) {
       store.dispatch(RefreshData(
         allCompanies: true,
         completer: Completer<Null>()
-          ..future.then<Null>(() {
+          ..future.then<Null>((_) {
             store.dispatch(SelectCompany(companyIndex: state.companies.length));
             store.dispatch(ViewDashboard(force: true));
 
             action!.completer!.complete();
-          } as FutureOr<Null> Function(Null)),
+          }),
       ));
     });
 
@@ -459,9 +459,9 @@ Middleware<AppState> _purgeData(AuthRepository repository) {
       store.dispatch(RefreshData(
           clearData: true,
           completer: Completer<Null>()
-            ..future.then<Null>(() {
+            ..future.then<Null>((_) {
               action.completer.complete(null);
-            } as FutureOr<Null> Function(Null))));
+            })));
     }).catchError((Object error) {
       store.dispatch(PurgeDataFailure(error));
       action.completer.completeError(error);
diff --git a/lib/redux/company_gateway/company_gateway_actions.dart b/lib/redux/company_gateway/company_gateway_actions.dart
index da4a61895..5f3c230fa 100644
--- a/lib/redux/company_gateway/company_gateway_actions.dart
+++ b/lib/redux/company_gateway/company_gateway_actions.dart
@@ -309,9 +309,9 @@ void handleCompanyGatewayAction(BuildContext? context,
     case EntityAction.disconnect:
       final completer =
           snackBarCompleter<Null>(context, localization!.disconnectedGateway);
-      completer.future.then<Null>(() {
+      completer.future.then<Null>((_) {
         store.dispatch(RefreshData());
-      } as FutureOr<Null> Function(Null));
+      });
       confirmCallback(
           context: context,
           callback: (_) {
diff --git a/lib/redux/document/document_actions.dart b/lib/redux/document/document_actions.dart
index 174cbe4cf..c6cca11cf 100644
--- a/lib/redux/document/document_actions.dart
+++ b/lib/redux/document/document_actions.dart
@@ -483,82 +483,67 @@ void handleDocumentAction(
                       context, AppLocalization.of(context)!.deletedDocument);
                   switch (document!.parentType) {
                     case EntityType.client:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadClient(clientId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store
+                          .dispatch(LoadClient(clientId: document.parentId))));
                       break;
                     case EntityType.credit:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadCredit(creditId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store
+                          .dispatch(LoadCredit(creditId: document.parentId))));
                       break;
                     case EntityType.expense:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadExpense(expenseId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store.dispatch(
+                          LoadExpense(expenseId: document.parentId))));
                       break;
                     case EntityType.group:
-                      completer.future.then<Null>((() => store
-                              .dispatch(LoadGroup(groupId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store
+                          .dispatch(LoadGroup(groupId: document.parentId))));
                       break;
                     case EntityType.invoice:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadInvoice(invoiceId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store.dispatch(
+                          LoadInvoice(invoiceId: document.parentId))));
                       break;
                     case EntityType.product:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadProduct(productId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store.dispatch(
+                          LoadProduct(productId: document.parentId))));
                       break;
                     case EntityType.project:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadProject(projectId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store.dispatch(
+                          LoadProject(projectId: document.parentId))));
                       break;
                     case EntityType.purchaseOrder:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadPurchaseOrder(
-                                  purchaseOrderId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store.dispatch(
+                          LoadPurchaseOrder(
+                              purchaseOrderId: document.parentId))));
                       break;
                     case EntityType.quote:
-                      completer.future.then<Null>((() => store
-                              .dispatch(LoadQuote(quoteId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store
+                          .dispatch(LoadQuote(quoteId: document.parentId))));
                       break;
                     case EntityType.recurringExpense:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadRecurringExpense(
-                                  recurringExpenseId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store.dispatch(
+                          LoadRecurringExpense(
+                              recurringExpenseId: document.parentId))));
                       break;
                     case EntityType.recurringInvoice:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadRecurringInvoice(
-                                  recurringInvoiceId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store.dispatch(
+                          LoadRecurringInvoice(
+                              recurringInvoiceId: document.parentId))));
                       break;
                     case EntityType.task:
-                      completer.future.then<Null>((() => store
-                              .dispatch(LoadTask(taskId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) =>
+                          store.dispatch(LoadTask(taskId: document.parentId))));
                       break;
                     case EntityType.vendor:
-                      completer.future.then<Null>((() => store.dispatch(
-                              LoadVendor(vendorId: document.parentId)))
-                          as FutureOr<Null> Function(Null));
+                      completer.future.then<Null>(((_) => store
+                          .dispatch(LoadVendor(vendorId: document.parentId))));
                       break;
                     default:
-                      completer.future.then<Null>((() =>
-                              store.dispatch(RefreshData()))
-                          as FutureOr<Null> Function(Null));
+                      completer.future
+                          .then<Null>(((_) => store.dispatch(RefreshData())));
                   }
 
-                  completer.future.then<Null>((() =>
-                          store.dispatch(RefreshData()))
-                      as FutureOr<Null> Function(Null));
+                  completer.future
+                      .then<Null>(((_) => store.dispatch(RefreshData())));
                   store.dispatch(DeleteDocumentRequest(
                     completer: completer,
                     documentIds: [document.id],
diff --git a/lib/ui/app/desktop_session_timeout.dart b/lib/ui/app/desktop_session_timeout.dart
index 2295df7de..cd113a4b6 100644
--- a/lib/ui/app/desktop_session_timeout.dart
+++ b/lib/ui/app/desktop_session_timeout.dart
@@ -90,11 +90,11 @@ class _DesktopSessionTimeoutState extends State<DesktopSessionTimeout> {
                       onPressed: () {
                         final store = StoreProvider.of<AppState>(context);
                         final completer = Completer<Null>();
-                        completer.future.then(() {
+                        completer.future.then<Null>((_) {
                           setState(() {
                             _isWarned = false;
                           });
-                        } as FutureOr<Null> Function(Null));
+                        });
                         store.dispatch(RefreshData(completer: completer));
                       },
                       child: Text(
diff --git a/lib/ui/app/dialogs/health_check_dialog.dart b/lib/ui/app/dialogs/health_check_dialog.dart
index e34e98f6e..c412172ae 100644
--- a/lib/ui/app/dialogs/health_check_dialog.dart
+++ b/lib/ui/app/dialogs/health_check_dialog.dart
@@ -88,9 +88,9 @@ class _HealthCheckDialogState extends State<HealthCheckDialog> {
     webClient.get(url, credentials.token).then((dynamic response) {
       store.dispatch(RefreshData(
           completer: Completer<Null>()
-            ..future.then<Null>(() {
+            ..future.then<Null>((_) {
               runCheck();
-            } as FutureOr<Null> Function(Null))));
+            })));
     }).catchError((dynamic error) {
       showErrorDialog(message: error);
     });
diff --git a/lib/ui/app/history_drawer.dart b/lib/ui/app/history_drawer.dart
index 35440be06..7b10f78d0 100644
--- a/lib/ui/app/history_drawer.dart
+++ b/lib/ui/app/history_drawer.dart
@@ -261,9 +261,9 @@ class _HistoryListTileState extends State<HistoryListTile> {
                   entities: [entity],
                   completer: state.prefState.isHistoryFloated
                       ? (Completer<Null>()
-                        ..future.then<Null>(() {
+                        ..future.then<Null>((_) {
                           Navigator.pop(context);
-                        } as FutureOr<Null> Function(Null)))
+                        }))
                       : null,
                 );
               },
diff --git a/lib/ui/app/menu_drawer_vm.dart b/lib/ui/app/menu_drawer_vm.dart
index 58f246c7c..ba8b6b9be 100644
--- a/lib/ui/app/menu_drawer_vm.dart
+++ b/lib/ui/app/menu_drawer_vm.dart
@@ -140,9 +140,9 @@ class MenuDrawerVM {
               final completer = snackBarCompleter<Null>(
                   context, AppLocalization.of(context)!.addedCompany,
                   shouldPop: true)
-                ..future.then<Null>(() {
+                ..future.then<Null>((_) {
                   AppBuilder.of(navigatorKey.currentContext!)!.rebuild();
-                } as FutureOr<Null> Function(Null));
+                });
 
               store
                   .dispatch(AddCompany(context: context, completer: completer));
diff --git a/lib/ui/app/tables/entity_list.dart b/lib/ui/app/tables/entity_list.dart
index 49b19df96..5292e42b5 100644
--- a/lib/ui/app/tables/entity_list.dart
+++ b/lib/ui/app/tables/entity_list.dart
@@ -470,9 +470,8 @@ class _EntityListState extends State<EntityList> {
                             entities: entities,
                             multiselect: true,
                             completer: Completer<Null>()
-                              ..future.then<Null>((() =>
-                                      widget.onClearMultiselect())
-                                  as FutureOr<Null> Function(Null)),
+                              ..future.then<Null>(
+                                  ((_) => widget.onClearMultiselect())),
                           );
                         },
                         onCancelPressed: (_) => widget.onClearMultiselect(),
diff --git a/lib/ui/auth/login_view.dart b/lib/ui/auth/login_view.dart
index ab4931cb3..88f4def43 100644
--- a/lib/ui/auth/login_view.dart
+++ b/lib/ui/auth/login_view.dart
@@ -184,13 +184,11 @@ class _LoginState extends State<LoginView> {
     }
 
     final Completer<Null> completer = Completer<Null>();
-    completer.future
-        .then<Null>(() {
+    completer.future.then<Null>((_) {
       setState(() {
         _loginError = '';
       });
-    } as FutureOr<Null> Function(Null))
-        .catchError((Object error) {
+    }).catchError((Object error) {
       setState(() {
         _buttonController.reset();
         _loginError = error.toString();
diff --git a/lib/ui/auth/login_vm.dart b/lib/ui/auth/login_vm.dart
index 2510ba069..0abf97c7a 100644
--- a/lib/ui/auth/login_vm.dart
+++ b/lib/ui/auth/login_vm.dart
@@ -184,8 +184,8 @@ class LoginVM {
                 provider: UserEntity.OAUTH_PROVIDER_GOOGLE,
                 oneTimePassword: oneTimePassword,
               ));
-              completer.future.then<Null>((() => _handleLogin(context: context))
-                  as FutureOr<Null> Function(Null));
+              completer.future
+                  .then<Null>(((_) => _handleLogin(context: context)));
             }
           });
           if (!signedIn) {
@@ -215,9 +215,8 @@ class LoginVM {
                 accessToken: accessToken,
                 provider: UserEntity.OAUTH_PROVIDER_GOOGLE,
               ));
-              completer.future.then<Null>((() =>
-                      _handleLogin(context: context, isSignUp: true))
-                  as FutureOr<Null> Function(Null));
+              completer.future.then<Null>(
+                  ((_) => _handleLogin(context: context, isSignUp: true)));
             }
           });
           if (!signedIn) {
@@ -249,8 +248,8 @@ class LoginVM {
               provider: UserEntity.OAUTH_PROVIDER_MICROSOFT,
               oneTimePassword: oneTimePassword,
             ));
-            completer.future.then<Null>((() => _handleLogin(context: context))
-                as FutureOr<Null> Function(Null));
+            completer.future
+                .then<Null>(((_) => _handleLogin(context: context)));
           }, (dynamic error) {
             completer.completeError(error);
           });
@@ -270,9 +269,8 @@ class LoginVM {
               provider: UserEntity.OAUTH_PROVIDER_MICROSOFT,
               accessToken: accessToken,
             ));
-            completer.future.then<Null>((() =>
-                    _handleLogin(context: context, isSignUp: true))
-                as FutureOr<Null> Function(Null));
+            completer.future.then<Null>(
+                ((_) => _handleLogin(context: context, isSignUp: true)));
           }, (dynamic error) {
             completer.completeError(error);
           });
@@ -311,8 +309,7 @@ class LoginVM {
             authCode: credentials.authorizationCode,
             idToken: credentials.identityToken,
           ));
-          completer.future.then<Null>((() => _handleLogin(context: context))
-              as FutureOr<Null> Function(Null));
+          completer.future.then<Null>(((_) => _handleLogin(context: context)));
         } catch (error) {
           completer.completeError(error);
           print('## onAppleLoginPressed: $error');
@@ -340,9 +337,8 @@ class LoginVM {
             firstName: credentials.givenName,
             lastName: credentials.familyName,
           ));
-          completer.future.then<Null>((() =>
-                  _handleLogin(context: context, isSignUp: true))
-              as FutureOr<Null> Function(Null));
+          completer.future.then<Null>(
+              ((_) => _handleLogin(context: context, isSignUp: true)));
         } catch (error) {
           completer.completeError(error);
           print('## onAppleSignUpPressed: $error');
@@ -363,9 +359,8 @@ class LoginVM {
           email: email.trim(),
           password: password.trim(),
         ));
-        completer.future.then<Null>((() =>
-                _handleLogin(context: context, isSignUp: true))
-            as FutureOr<Null> Function(Null));
+        completer.future.then<Null>(
+            ((_) => _handleLogin(context: context, isSignUp: true)));
       },
       onRecoverPressed: (
         BuildContext context,
diff --git a/lib/ui/company_gateway/company_gateway_screen.dart b/lib/ui/company_gateway/company_gateway_screen.dart
index 179623fae..1e8d0fd26 100644
--- a/lib/ui/company_gateway/company_gateway_screen.dart
+++ b/lib/ui/company_gateway/company_gateway_screen.dart
@@ -72,9 +72,8 @@ class CompanyGatewayScreen extends StatelessWidget {
                       entities: companyGateways,
                       multiselect: true,
                       completer: Completer<Null>()
-                        ..future.then<Null>((() => store
-                                .dispatch(ClearCompanyGatewayMultiselect()))
-                            as FutureOr<Null> Function(Null)),
+                        ..future.then<Null>(((_) =>
+                            store.dispatch(ClearCompanyGatewayMultiselect()))),
                     );
                   },
             onCancelPressed: (context) =>
diff --git a/lib/ui/credit/credit_email_vm.dart b/lib/ui/credit/credit_email_vm.dart
index 7d5ed1706..9b745e2c5 100644
--- a/lib/ui/credit/credit_email_vm.dart
+++ b/lib/ui/credit/credit_email_vm.dart
@@ -92,9 +92,9 @@ class EmailCreditVM extends EmailEntityVM {
             context, AppLocalization.of(context)!.emailedCredit,
             shouldPop: isMobile(context));
         if (!isMobile(context)) {
-          completer.future.then<Null>(() {
+          completer.future.then<Null>((_) {
             viewEntity(entity: credit);
-          } as FutureOr<Null> Function(Null));
+          });
         }
         store.dispatch(EmailCreditRequest(
           completer: completer,
diff --git a/lib/ui/credit/edit/credit_edit_details_vm.dart b/lib/ui/credit/edit/credit_edit_details_vm.dart
index 94297e2f2..423ddf65d 100644
--- a/lib/ui/credit/edit/credit_edit_details_vm.dart
+++ b/lib/ui/credit/edit/credit_edit_details_vm.dart
@@ -103,9 +103,9 @@ class CreditEditDetailsVM extends EntityEditDetailsVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(UpdateCurrentRoute(CreditEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(CreditEditScreen.route));
         });
diff --git a/lib/ui/expense/edit/expense_edit_vm.dart b/lib/ui/expense/edit/expense_edit_vm.dart
index d1e9d8ff8..4b9e8cf27 100644
--- a/lib/ui/expense/edit/expense_edit_vm.dart
+++ b/lib/ui/expense/edit/expense_edit_vm.dart
@@ -120,9 +120,9 @@ class ExpenseEditVM extends AbstractExpenseEditVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(UpdateCurrentRoute(ExpenseEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(ExpenseEditScreen.route));
         });
@@ -134,9 +134,9 @@ class ExpenseEditVM extends AbstractExpenseEditVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(UpdateCurrentRoute(ExpenseEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity expense) {
           store.dispatch(UpdateCurrentRoute(ExpenseEditScreen.route));
         });
diff --git a/lib/ui/invoice/edit/invoice_edit_details_vm.dart b/lib/ui/invoice/edit/invoice_edit_details_vm.dart
index 3e8391cee..d686978c3 100644
--- a/lib/ui/invoice/edit/invoice_edit_details_vm.dart
+++ b/lib/ui/invoice/edit/invoice_edit_details_vm.dart
@@ -131,9 +131,9 @@ class InvoiceEditDetailsVM extends EntityEditDetailsVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(UpdateCurrentRoute(InvoiceEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(InvoiceEditScreen.route));
         });
diff --git a/lib/ui/invoice/invoice_email_vm.dart b/lib/ui/invoice/invoice_email_vm.dart
index b26f43986..f6306ae8d 100644
--- a/lib/ui/invoice/invoice_email_vm.dart
+++ b/lib/ui/invoice/invoice_email_vm.dart
@@ -113,9 +113,9 @@ class EmailInvoiceVM extends EmailEntityVM {
             context, AppLocalization.of(context)!.emailedInvoice,
             shouldPop: isMobile(context));
         if (!isMobile(context)) {
-          completer.future.then<Null>(() {
+          completer.future.then<Null>((_) {
             viewEntity(entity: invoice);
-          } as FutureOr<Null> Function(Null));
+          });
         }
         store.dispatch(EmailInvoiceRequest(
           completer: completer,
diff --git a/lib/ui/project/edit/project_edit_vm.dart b/lib/ui/project/edit/project_edit_vm.dart
index b6d2d2fa4..1287cb1aa 100644
--- a/lib/ui/project/edit/project_edit_vm.dart
+++ b/lib/ui/project/edit/project_edit_vm.dart
@@ -88,9 +88,9 @@ class ProjectEditVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(UpdateCurrentRoute(ProjectEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(ProjectEditScreen.route));
         });
diff --git a/lib/ui/purchase_order/edit/purchase_order_edit_details_vm.dart b/lib/ui/purchase_order/edit/purchase_order_edit_details_vm.dart
index 36affb5ca..1791c1afb 100644
--- a/lib/ui/purchase_order/edit/purchase_order_edit_details_vm.dart
+++ b/lib/ui/purchase_order/edit/purchase_order_edit_details_vm.dart
@@ -102,10 +102,10 @@ class PurchaseOrderEditDetailsVM extends EntityEditDetailsVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(
                     UpdateCurrentRoute(PurchaseOrderEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(PurchaseOrderEditScreen.route));
         });
diff --git a/lib/ui/purchase_order/purchase_order_email_vm.dart b/lib/ui/purchase_order/purchase_order_email_vm.dart
index 3dbed5b93..d3d66e817 100644
--- a/lib/ui/purchase_order/purchase_order_email_vm.dart
+++ b/lib/ui/purchase_order/purchase_order_email_vm.dart
@@ -90,9 +90,9 @@ class EmailPurchaseOrderVM extends EmailEntityVM {
             context, AppLocalization.of(context)!.emailedPurchaseOrder,
             shouldPop: isMobile(context));
         if (!isMobile(context)) {
-          completer.future.then<Null>(() {
+          completer.future.then<Null>((_) {
             viewEntity(entity: purchaseOrder);
-          } as FutureOr<Null> Function(Null));
+          });
         }
         store.dispatch(EmailPurchaseOrderRequest(
           completer: completer,
diff --git a/lib/ui/quote/edit/quote_edit_details_vm.dart b/lib/ui/quote/edit/quote_edit_details_vm.dart
index c0213fa18..034d93337 100644
--- a/lib/ui/quote/edit/quote_edit_details_vm.dart
+++ b/lib/ui/quote/edit/quote_edit_details_vm.dart
@@ -102,9 +102,9 @@ class QuoteEditDetailsVM extends EntityEditDetailsVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(UpdateCurrentRoute(QuoteEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(QuoteEditScreen.route));
         });
diff --git a/lib/ui/quote/quote_email_vm.dart b/lib/ui/quote/quote_email_vm.dart
index 4fdcffafb..9453128ce 100644
--- a/lib/ui/quote/quote_email_vm.dart
+++ b/lib/ui/quote/quote_email_vm.dart
@@ -89,9 +89,9 @@ class EmailQuoteVM extends EmailEntityVM {
             context, AppLocalization.of(context)!.emailedQuote,
             shouldPop: isMobile(context));
         if (!isMobile(context)) {
-          completer.future.then<Null>(() {
+          completer.future.then<Null>((_) {
             viewEntity(entity: quote);
-          } as FutureOr<Null> Function(Null));
+          });
         }
         store.dispatch(EmailQuoteRequest(
           completer: completer,
diff --git a/lib/ui/recurring_expense/edit/recurring_expense_edit_vm.dart b/lib/ui/recurring_expense/edit/recurring_expense_edit_vm.dart
index c0326b0e8..a640fac81 100644
--- a/lib/ui/recurring_expense/edit/recurring_expense_edit_vm.dart
+++ b/lib/ui/recurring_expense/edit/recurring_expense_edit_vm.dart
@@ -90,10 +90,10 @@ class RecurringExpenseEditVM extends AbstractExpenseEditVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(
                     UpdateCurrentRoute(RecurringExpenseEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(RecurringExpenseEditScreen.route));
         });
@@ -105,10 +105,10 @@ class RecurringExpenseEditVM extends AbstractExpenseEditVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(
                     UpdateCurrentRoute(RecurringExpenseEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity expense) {
           store.dispatch(UpdateCurrentRoute(RecurringExpenseEditScreen.route));
         });
diff --git a/lib/ui/recurring_invoice/edit/recurring_invoice_edit_details_vm.dart b/lib/ui/recurring_invoice/edit/recurring_invoice_edit_details_vm.dart
index 433685a00..555b881f3 100644
--- a/lib/ui/recurring_invoice/edit/recurring_invoice_edit_details_vm.dart
+++ b/lib/ui/recurring_invoice/edit/recurring_invoice_edit_details_vm.dart
@@ -105,10 +105,10 @@ class RecurringInvoiceEditDetailsVM extends EntityEditDetailsVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(
                     UpdateCurrentRoute(RecurringInvoiceEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(RecurringInvoiceEditScreen.route));
         });
diff --git a/lib/ui/settings/account_management_vm.dart b/lib/ui/settings/account_management_vm.dart
index ef089df80..61947a3fb 100644
--- a/lib/ui/settings/account_management_vm.dart
+++ b/lib/ui/settings/account_management_vm.dart
@@ -73,8 +73,7 @@ class AccountManagementVM {
 
           final companyLength = state.companies.length;
           final deleteCompleter = Completer<Null>()
-            ..future
-                .then<Null>(() {
+            ..future.then<Null>((_) {
               final context = navigatorKey.currentContext;
               final state = store.state;
               if (companyLength == 1) {
@@ -87,7 +86,7 @@ class AccountManagementVM {
                 final index = selectedCompanyIndex == 0 ? 1 : 0;
                 store.dispatch(SelectCompany(companyIndex: index));
                 final refreshCompleter = Completer<Null>()
-                  ..future.then<Null>(() {
+                  ..future.then<Null>((_) {
                     store.dispatch(SelectCompany(companyIndex: 0));
                     store.dispatch(ViewDashboard());
                     AppBuilder.of(navigatorKey.currentContext!)!.rebuild();
@@ -95,12 +94,11 @@ class AccountManagementVM {
                     if (Navigator.of(context!).canPop()) {
                       Navigator.of(context).pop();
                     }
-                  } as FutureOr<Null> Function(Null));
+                  });
                 store.dispatch(
                     RefreshData(clearData: true, completer: refreshCompleter));
               }
-            } as FutureOr<Null> Function(Null))
-                .catchError((Object error) {
+            }).catchError((Object error) {
               if (Navigator.of(navigatorKey.currentContext!).canPop()) {
                 Navigator.of(navigatorKey.currentContext!).pop();
               }
diff --git a/lib/ui/settings/client_portal_vm.dart b/lib/ui/settings/client_portal_vm.dart
index 39a07c3fa..f5e4d4d7d 100644
--- a/lib/ui/settings/client_portal_vm.dart
+++ b/lib/ui/settings/client_portal_vm.dart
@@ -82,10 +82,10 @@ class ClientPortalVM {
                   final oldSubdomain = state.company!.subdomain;
                   final newSubdomain = settingsUIState.company.subdomain;
                   if (oldSubdomain != newSubdomain) {
-                    completer.future.then<Null>(() {
+                    completer.future.then<Null>((_) {
                       showRefreshDataDialog(
                           context: navigatorKey.currentContext!);
-                    } as FutureOr<Null> Function(Null));
+                    });
                   }
 
                   store.dispatch(SaveCompanyRequest(
diff --git a/lib/ui/settings/invoice_design_vm.dart b/lib/ui/settings/invoice_design_vm.dart
index aa284e0fa..c6d010003 100644
--- a/lib/ui/settings/invoice_design_vm.dart
+++ b/lib/ui/settings/invoice_design_vm.dart
@@ -83,7 +83,7 @@ class InvoiceDesignVM {
               case EntityType.company:
                 final completer = snackBarCompleter<Null>(
                     context, AppLocalization.of(context)!.savedSettings)
-                  ..future.then<Null>(() {
+                  ..future.then<Null>((_) {
                     final webClient = WebClient();
                     final credentials = state.credentials;
                     final url = '${credentials.url}/designs/set/default';
@@ -106,7 +106,7 @@ class InvoiceDesignVM {
                         showErrorDialog(message: '$error');
                       });
                     });
-                  } as FutureOr<Null> Function(Null));
+                  });
                 store.dispatch(SaveCompanyRequest(
                     completer: completer, company: settingsUIState.company));
                 break;
diff --git a/lib/ui/settings/localization_vm.dart b/lib/ui/settings/localization_vm.dart
index 4dc35ac91..f33177ee1 100644
--- a/lib/ui/settings/localization_vm.dart
+++ b/lib/ui/settings/localization_vm.dart
@@ -75,14 +75,14 @@ class LocalizationSettingsVM {
                 final appBuilder = AppBuilder.of(context);
                 final completer = snackBarCompleter<Null>(
                     context, AppLocalization.of(context)!.savedSettings)
-                  ..future.then<Null>(() {
+                  ..future.then<Null>((_) {
                     appBuilder!.rebuild();
                     store.dispatch(RefreshData(
                         includeStatic: true,
                         completer: Completer<dynamic>()
                           ..future
                               .then((dynamic value) => appBuilder.rebuild())));
-                  } as FutureOr<Null> Function(Null));
+                  });
                 store.dispatch(SaveCompanyRequest(
                     completer: completer, company: settingsUIState.company));
                 break;
diff --git a/lib/ui/settings/settings_wizard.dart b/lib/ui/settings/settings_wizard.dart
index a7f4cf5ce..1a9ef856c 100644
--- a/lib/ui/settings/settings_wizard.dart
+++ b/lib/ui/settings/settings_wizard.dart
@@ -146,18 +146,15 @@ class _SettingsWizardState extends State<SettingsWizard> {
         callback: (password, idToken) {
           final localization = AppLocalization.of(context);
           final completer = Completer<Null>();
-          completer.future
-              .then<Null>(() {
+          completer.future.then<Null>((_) {
             final toastCompleter =
                 snackBarCompleter<Null>(context, localization!.savedSettings);
-            toastCompleter.future
-                .then<Null>(() {
+            toastCompleter.future.then<Null>((_) {
               setState(() {
                 _isSaving = false;
                 _showLogo = true;
               });
-            } as FutureOr<Null> Function(Null))
-                .catchError((Object error) {
+            }).catchError((Object error) {
               setState(() {
                 _isSaving = false;
               });
@@ -174,8 +171,7 @@ class _SettingsWizardState extends State<SettingsWizard> {
                 ),
               ),
             );
-          } as FutureOr<Null> Function(Null))
-              .catchError((Object error) {
+          }).catchError((Object error) {
             setState(() => _isSaving = false);
           });
 
diff --git a/lib/ui/settings/templates_and_reminders_vm.dart b/lib/ui/settings/templates_and_reminders_vm.dart
index 5ea565c09..525ec422c 100644
--- a/lib/ui/settings/templates_and_reminders_vm.dart
+++ b/lib/ui/settings/templates_and_reminders_vm.dart
@@ -96,8 +96,7 @@ class TemplatesAndRemindersVM {
             case EntityType.company:
               final completer = snackBarCompleter<Null>(
                   context, AppLocalization.of(context)!.savedSettings);
-              completer.future.then<Null>(
-                  (() => callback()) as FutureOr<Null> Function(Null));
+              completer.future.then<Null>(((_) => callback()));
               store.dispatch(SaveCompanyRequest(
                   completer: completer, company: settingsUIState.company));
               break;
diff --git a/lib/ui/settings/user_details_vm.dart b/lib/ui/settings/user_details_vm.dart
index 6c25294a9..f3209596d 100644
--- a/lib/ui/settings/user_details_vm.dart
+++ b/lib/ui/settings/user_details_vm.dart
@@ -176,9 +176,9 @@ class UserDetailsVM {
                   callback: (password, idToken) {
                     final completer = snackBarCompleter<Null>(context,
                         AppLocalization.of(context)!.disconnectedGoogle);
-                    completer.future.then<Null>(() {
+                    completer.future.then<Null>((_) {
                       GoogleOAuth.disconnect();
-                    } as FutureOr<Null> Function(Null));
+                    });
                     store.dispatch(
                       DisconnecOAuthUserRequest(
                         user: state.user,
@@ -315,7 +315,7 @@ class UserDetailsVM {
           final appBuilder = AppBuilder.of(context);
           final origUserSettings = state.userCompany!.settings;
 
-          completer.future.then<Null>(() async {
+          completer.future.then<Null>((_) async {
             final newUserSettings = store.state.userCompany!.settings!;
             if (origUserSettings!.includeDeletedClients !=
                     newUserSettings.includeDeletedClients ||
@@ -338,7 +338,7 @@ class UserDetailsVM {
             }
 
             appBuilder!.rebuild();
-          } as FutureOr<Null> Function(Null));
+          });
 
           confirmCallback(
               context: context,
diff --git a/lib/ui/task/edit/task_edit_details_vm.dart b/lib/ui/task/edit/task_edit_details_vm.dart
index a77856f2c..c9fdfd728 100644
--- a/lib/ui/task/edit/task_edit_details_vm.dart
+++ b/lib/ui/task/edit/task_edit_details_vm.dart
@@ -82,9 +82,9 @@ class TaskEditDetailsVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(UpdateCurrentRoute(TaskEditDetailsScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(TaskEditDetailsScreen.route));
         });
@@ -107,9 +107,9 @@ class TaskEditDetailsVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(UpdateCurrentRoute(TaskEditDetailsScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(TaskEditDetailsScreen.route));
         });
diff --git a/lib/ui/task_status/task_status_screen.dart b/lib/ui/task_status/task_status_screen.dart
index 463a05981..9a9fa049a 100644
--- a/lib/ui/task_status/task_status_screen.dart
+++ b/lib/ui/task_status/task_status_screen.dart
@@ -78,9 +78,8 @@ class TaskStatusScreen extends StatelessWidget {
                 entities: taskStatusIds,
                 multiselect: true,
                 completer: Completer<Null>()
-                  ..future.then<Null>((() =>
-                          store.dispatch(ClearTaskStatusMultiselect()))
-                      as FutureOr<Null> Function(Null)),
+                  ..future.then<Null>(
+                      ((_) => store.dispatch(ClearTaskStatusMultiselect()))),
               );
             },
             label: localization!.actions,
diff --git a/lib/ui/transaction/edit/transaction_edit_vm.dart b/lib/ui/transaction/edit/transaction_edit_vm.dart
index a39a26e19..be1a8c48d 100644
--- a/lib/ui/transaction/edit/transaction_edit_vm.dart
+++ b/lib/ui/transaction/edit/transaction_edit_vm.dart
@@ -110,9 +110,9 @@ class TransactionEditVM {
             force: true,
             completer: completer,
             cancelCompleter: Completer<Null>()
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 store.dispatch(UpdateCurrentRoute(TransactionEditScreen.route));
-              } as FutureOr<Null> Function(Null)));
+              }));
         completer.future.then((SelectableEntity client) {
           store.dispatch(UpdateCurrentRoute(TransactionEditScreen.route));
         });
diff --git a/lib/ui/transaction/view/transaction_view.dart b/lib/ui/transaction/view/transaction_view.dart
index e7fac79df..c8375c9de 100644
--- a/lib/ui/transaction/view/transaction_view.dart
+++ b/lib/ui/transaction/view/transaction_view.dart
@@ -1109,10 +1109,10 @@ class _MatchWithdrawalsState extends State<_MatchWithdrawals> {
                             force: true,
                             completer: completer,
                             cancelCompleter: Completer<Null>()
-                              ..future.then<Null>(() {
+                              ..future.then<Null>((_) {
                                 store.dispatch(UpdateCurrentRoute(
                                     TransactionScreen.route));
-                              } as FutureOr<Null> Function(Null)));
+                              }));
                         completer.future.then((SelectableEntity vendor) {
                           store.dispatch(SaveTransactionSuccess(transaction
                               .rebuild((b) => b..pendingVendorId = vendor.id)));
@@ -1193,10 +1193,10 @@ class _MatchWithdrawalsState extends State<_MatchWithdrawals> {
                             force: true,
                             completer: completer,
                             cancelCompleter: Completer<Null>()
-                              ..future.then<Null>(() {
+                              ..future.then<Null>((_) {
                                 store.dispatch(UpdateCurrentRoute(
                                     TransactionScreen.route));
-                              } as FutureOr<Null> Function(Null)));
+                              }));
                         completer.future.then((SelectableEntity category) {
                           store.dispatch(SaveTransactionSuccess(
                               transaction.rebuild(
diff --git a/lib/ui/transaction/view/transaction_view_vm.dart b/lib/ui/transaction/view/transaction_view_vm.dart
index b92749972..a690142ed 100644
--- a/lib/ui/transaction/view/transaction_view_vm.dart
+++ b/lib/ui/transaction/view/transaction_view_vm.dart
@@ -118,14 +118,14 @@ class TransactionViewVM {
           ConvertTransactionsToExpensesRequest(
             snackBarCompleter<Null>(
                 context, AppLocalization.of(context)!.convertedTransaction)
-              ..future.then<Null>(() {
+              ..future.then<Null>((_) {
                 if (state.transactionListState.isInMultiselect()) {
                   store.dispatch(ClearTransactionMultiselect());
                   if (store.state.prefState.isPreviewVisible) {
                     store.dispatch(TogglePreviewSidebar());
                   }
                 }
-              } as FutureOr<Null> Function(Null)),
+              }),
             transactionIds,
             vendorId,
             categoryId,
diff --git a/lib/utils/completers.dart b/lib/utils/completers.dart
index 050417e23..f574c07d4 100644
--- a/lib/utils/completers.dart
+++ b/lib/utils/completers.dart
@@ -46,11 +46,9 @@ Completer<T> snackBarCompleter<T>(
 Completer<Null> popCompleter(BuildContext context, dynamic result) {
   final Completer<Null> completer = Completer<Null>();
 
-  completer.future
-      .then<Null>(() {
+  completer.future.then<Null>((_) {
     Navigator.of(context).pop<dynamic>(result);
-  } as FutureOr<Null> Function(Null))
-      .catchError((Object error) {
+  }).catchError((Object error) {
     showDialog<ErrorDialog>(
         context: navigatorKey.currentContext!,
         builder: (BuildContext context) {