diff --git a/webapp/packages/core/src/root/ServerService.ts b/webapp/packages/core/src/root/ServerService.ts
index 6dde91fc2b..e87d172b6a 100644
--- a/webapp/packages/core/src/root/ServerService.ts
+++ b/webapp/packages/core/src/root/ServerService.ts
@@ -33,8 +33,7 @@ export class ServerService {
       this.settings.clear();
       parseJSONFlat(
         serverConfig.productConfiguration,
-        this.settings.setSelfValue.bind(this.settings),
-        undefined
+        this.settings.setSelfValue.bind(this.settings)
       );
     }
     return serverConfig;
diff --git a/webapp/packages/core/src/sdk/GQLErrorCatcher.ts b/webapp/packages/core/src/sdk/GQLErrorCatcher.ts
new file mode 100644
index 0000000000..380d2f3e87
--- /dev/null
+++ b/webapp/packages/core/src/sdk/GQLErrorCatcher.ts
@@ -0,0 +1,34 @@
+/*
+ * cloudbeaver - Cloud Database Manager
+ * Copyright (C) 2020 DBeaver Corp and others
+ *
+ * Licensed under the Apache License, Version 2.0.
+ * you may not use this file except in compliance with the License.
+ */
+
+import { observable, action } from 'mobx';
+
+import { GQLError } from './GQLError';
+
+export class GQLErrorCatcher {
+  @observable hasDetails = false
+  @observable responseMessage: string | null = null
+  @observable exception: GQLError | null = null;
+
+  @action catch(exception: any): boolean {
+    if (exception instanceof GQLError) {
+      this.responseMessage = exception.errorText;
+      this.hasDetails = exception.hasDetails();
+      this.exception = exception;
+      return true;
+    }
+    this.clear();
+    return false;
+  }
+
+  @action clear() {
+    this.hasDetails = false;
+    this.responseMessage = null;
+    this.exception = null;
+  }
+}
diff --git a/webapp/packages/core/src/sdk/index.ts b/webapp/packages/core/src/sdk/index.ts
index 11de1dd097..2b9ebec5ed 100644
--- a/webapp/packages/core/src/sdk/index.ts
+++ b/webapp/packages/core/src/sdk/index.ts
@@ -5,3 +5,4 @@ export * from './GQLError';
 export * from './ServerInternalError';
 export * from './CachedResource';
 export * from './EServerErrorCode';
+export * from './GQLErrorCatcher';
diff --git a/webapp/packages/custom-connection-plugin/src/CustomConnection/ConnectionFormDialog/ConnectionFormDialog.tsx b/webapp/packages/custom-connection-plugin/src/CustomConnection/ConnectionFormDialog/ConnectionFormDialog.tsx
index 0ef2030383..b276525b51 100644
--- a/webapp/packages/custom-connection-plugin/src/CustomConnection/ConnectionFormDialog/ConnectionFormDialog.tsx
+++ b/webapp/packages/custom-connection-plugin/src/CustomConnection/ConnectionFormDialog/ConnectionFormDialog.tsx
@@ -24,7 +24,6 @@ import { ConnectionFormDialogController } from './ConnectionFormDialogController
 import { ConnectionFormDialogFooter } from './ConnectionFormDialogFooter';
 import { DriverProperties } from './DriverProperties/DriverProperties';
 
-
 const styles = composes(
   css`
     BaseTab {
@@ -149,10 +148,10 @@ export const ConnectionFormDialog = observer(
             />
           </BaseTabPanel>
         </SubmittingForm>
-        {controller.responseMessage && (
+        {controller.error.responseMessage && (
           <ErrorMessage
-            text={controller.responseMessage}
-            hasDetails={controller.hasDetails}
+            text={controller.error.responseMessage}
+            hasDetails={controller.error.hasDetails}
             onShowDetails={controller.onShowDetails}
           />
         )}
diff --git a/webapp/packages/custom-connection-plugin/src/CustomConnection/ConnectionFormDialog/ConnectionFormDialogController.ts b/webapp/packages/custom-connection-plugin/src/CustomConnection/ConnectionFormDialog/ConnectionFormDialogController.ts
index 26648662a4..4c04ceaed7 100644
--- a/webapp/packages/custom-connection-plugin/src/CustomConnection/ConnectionFormDialog/ConnectionFormDialogController.ts
+++ b/webapp/packages/custom-connection-plugin/src/CustomConnection/ConnectionFormDialog/ConnectionFormDialogController.ts
@@ -12,7 +12,7 @@ import { DBDriver, ErrorDetailsDialog } from '@dbeaver/core/app';
 import { injectable, IInitializableController, IDestructibleController } from '@dbeaver/core/di';
 import { CommonDialogService } from '@dbeaver/core/dialogs';
 import { NotificationService } from '@dbeaver/core/eventsLog';
-import { ConnectionConfig, GQLError } from '@dbeaver/core/sdk';
+import { ConnectionConfig, GQLErrorCatcher } from '@dbeaver/core/sdk';
 
 import { CustomConnectionService } from '../../CustomConnectionService';
 
@@ -39,10 +39,7 @@ implements IInitializableController, IDestructibleController {
     url: '',
     properties: {},
   }
-  @observable hasDetails = false
-  @observable responseMessage: string | null = null
-
-  private exception: GQLError | null = null;
+  readonly error = new GQLErrorCatcher();
   private onClose!: () => void
   private isDistructed = false;
 
@@ -70,7 +67,7 @@ implements IInitializableController, IDestructibleController {
 
   onTestConnection = async () => {
     this.isConnecting = true;
-    this.clearError();
+    this.error.clear();
     try {
       await this.customConnectionService.testConnectionAsync(this.getConnectionConfig());
 
@@ -84,7 +81,7 @@ implements IInitializableController, IDestructibleController {
 
   onCreateConnection = async () => {
     this.isConnecting = true;
-    this.clearError();
+    this.error.clear();
     try {
       const connection = await this.customConnectionService.createConnectionAsync(this.getConnectionConfig());
 
@@ -98,8 +95,8 @@ implements IInitializableController, IDestructibleController {
   }
 
   onShowDetails = () => {
-    if (this.exception) {
-      this.commonDialogService.open(ErrorDetailsDialog, this.exception);
+    if (this.error.exception) {
+      this.commonDialogService.open(ErrorDetailsDialog, this.error.exception);
     }
   }
 
@@ -144,12 +141,6 @@ implements IInitializableController, IDestructibleController {
     this.config.properties = {};
   }
 
-  private clearError() {
-    this.responseMessage = null;
-    this.hasDetails = false;
-    this.exception = null;
-  }
-
   /**
    * Creates connection name based on connection url
    * @param defaultName default connection name if url parsing failed
@@ -175,11 +166,7 @@ implements IInitializableController, IDestructibleController {
   }
 
   private showError(exception: Error, message: string) {
-    if (exception instanceof GQLError && !this.isDistructed) {
-      this.responseMessage = exception.errorText;
-      this.hasDetails = exception.hasDetails();
-      this.exception = exception;
-    } else {
+    if (!this.error.catch(exception) || this.isDistructed) {
       this.notificationService.logException(exception, message);
     }
   }
diff --git a/webapp/packages/custom-connection-plugin/src/CustomConnection/CustomConnectionDialog.tsx b/webapp/packages/custom-connection-plugin/src/CustomConnection/CustomConnectionDialog.tsx
index 8df2c23d58..b0d07b4909 100644
--- a/webapp/packages/custom-connection-plugin/src/CustomConnection/CustomConnectionDialog.tsx
+++ b/webapp/packages/custom-connection-plugin/src/CustomConnection/CustomConnectionDialog.tsx
@@ -9,7 +9,7 @@
 import { observer } from 'mobx-react';
 
 import { useController } from '@dbeaver/core/di';
-import { DialogComponent, DialogComponentProps } from '@dbeaver/core/dialogs';
+import { DialogComponent } from '@dbeaver/core/dialogs';
 import { useTranslate } from '@dbeaver/core/localization';
 
 import { ConnectionFormDialog } from './ConnectionFormDialog/ConnectionFormDialog';
@@ -17,7 +17,7 @@ import { CustomConnectionController, ConnectionStep } from './CustomConnectionCo
 import { DriverSelectorDialog } from './DriverSelectorDialog/DriverSelectorDialog';
 
 export const CustomConnectionDialog: DialogComponent<null, null> = observer(
-  function CustomConnectionDialog(props: DialogComponentProps<null, null>) {
+  function CustomConnectionDialog(props) {
     const controller = useController(CustomConnectionController);
     let title = useTranslate('basicConnection_connectionDialog_newConnection');