diff --git a/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/append.test.tsx b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/append.test.tsx
new file mode 100644
index 0000000000000..af3651525d6a3
--- /dev/null
+++ b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/append.test.tsx
@@ -0,0 +1,118 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import { act } from 'react-dom/test-utils';
+import { setup, SetupResult, getProcessorValue } from './processor.helpers';
+
+const APPEND_TYPE = 'append';
+
+describe('Processor: Append', () => {
+  let onUpdate: jest.Mock;
+  let testBed: SetupResult;
+
+  beforeAll(() => {
+    jest.useFakeTimers();
+  });
+
+  afterAll(() => {
+    jest.useRealTimers();
+  });
+
+  beforeEach(async () => {
+    onUpdate = jest.fn();
+
+    await act(async () => {
+      testBed = await setup({
+        value: {
+          processors: [],
+        },
+        onFlyoutOpen: jest.fn(),
+        onUpdate,
+      });
+    });
+    testBed.component.update();
+    const {
+      actions: { addProcessor, addProcessorType },
+    } = testBed;
+    // Open the processor flyout
+    addProcessor();
+
+    // Add type (the other fields are not visible until a type is selected)
+    await addProcessorType(APPEND_TYPE);
+  });
+
+  test('prevents form submission if required fields are not provided', async () => {
+    const {
+      actions: { saveNewProcessor },
+      form,
+    } = testBed;
+
+    // Click submit button with only the type defined
+    await saveNewProcessor();
+
+    // Expect form error as "field" and "value" are required parameters
+    expect(form.getErrorsMessages()).toEqual([
+      'A field value is required.',
+      'A value is required.',
+    ]);
+  });
+
+  test('saves with required parameter values', async () => {
+    const {
+      actions: { saveNewProcessor },
+      form,
+      find,
+      component,
+    } = testBed;
+
+    // Add "field" value (required)
+    form.setInputValue('fieldNameField.input', 'field_1');
+
+    await act(async () => {
+      find('appendValueField.input').simulate('change', [{ label: 'Some_Value' }]);
+    });
+    component.update();
+
+    // Save the field
+    await saveNewProcessor();
+
+    const processors = getProcessorValue(onUpdate, APPEND_TYPE);
+    expect(processors[0].append).toEqual({
+      field: 'field_1',
+      value: ['Some_Value'],
+    });
+  });
+
+  test('allows optional parameters to be set', async () => {
+    const {
+      actions: { saveNewProcessor },
+      form,
+      find,
+      component,
+    } = testBed;
+
+    // Add "field" value (required)
+    form.setInputValue('fieldNameField.input', 'field_1');
+
+    // Set optional parameteres
+    await act(async () => {
+      find('appendValueField.input').simulate('change', [{ label: 'Some_Value' }]);
+      component.update();
+    });
+
+    form.toggleEuiSwitch('ignoreFailureSwitch.input');
+    // Save the field with new changes
+    await saveNewProcessor();
+
+    const processors = getProcessorValue(onUpdate, APPEND_TYPE);
+    expect(processors[0].append).toEqual({
+      field: 'field_1',
+      ignore_failure: true,
+      value: ['Some_Value'],
+    });
+  });
+});
diff --git a/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/bytes.test.tsx b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/bytes.test.tsx
index af4f6e468ca36..51117c3b517f9 100644
--- a/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/bytes.test.tsx
+++ b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/bytes.test.tsx
@@ -35,24 +35,21 @@ describe('Processor: Bytes', () => {
       });
     });
     testBed.component.update();
-  });
-
-  test('prevents form submission if required fields are not provided', async () => {
     const {
-      actions: { addProcessor, saveNewProcessor, addProcessorType },
-      form,
+      actions: { addProcessor, addProcessorType },
     } = testBed;
-
-    // Open flyout to add new processor
+    // Open the processor flyout
     addProcessor();
-    // Click submit button without entering any fields
-    await saveNewProcessor();
-
-    // Expect form error as a processor type is required
-    expect(form.getErrorsMessages()).toEqual(['A type is required.']);
 
     // Add type (the other fields are not visible until a type is selected)
     await addProcessorType(BYTES_TYPE);
+  });
+
+  test('prevents form submission if required fields are not provided', async () => {
+    const {
+      actions: { saveNewProcessor },
+      form,
+    } = testBed;
 
     // Click submit button with only the type defined
     await saveNewProcessor();
@@ -61,16 +58,12 @@ describe('Processor: Bytes', () => {
     expect(form.getErrorsMessages()).toEqual(['A field value is required.']);
   });
 
-  test('saves with default parameter values', async () => {
+  test('saves with required parameter values', async () => {
     const {
-      actions: { addProcessor, saveNewProcessor, addProcessorType },
+      actions: { saveNewProcessor },
       form,
     } = testBed;
 
-    // Open flyout to add new processor
-    addProcessor();
-    // Add type (the other fields are not visible until a type is selected)
-    await addProcessorType(BYTES_TYPE);
     // Add "field" value (required)
     form.setInputValue('fieldNameField.input', 'field_1');
     // Save the field
@@ -84,14 +77,10 @@ describe('Processor: Bytes', () => {
 
   test('allows optional parameters to be set', async () => {
     const {
-      actions: { addProcessor, addProcessorType, saveNewProcessor },
+      actions: { saveNewProcessor },
       form,
     } = testBed;
 
-    // Open flyout to add new processor
-    addProcessor();
-    // Add type (the other fields are not visible until a type is selected)
-    await addProcessorType(BYTES_TYPE);
     // Add "field" value (required)
     form.setInputValue('fieldNameField.input', 'field_1');
 
diff --git a/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/processor.helpers.tsx b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/processor.helpers.tsx
index 8616241a43d8d..68f494a56af5d 100644
--- a/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/processor.helpers.tsx
+++ b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/processor.helpers.tsx
@@ -137,6 +137,7 @@ type TestSubject =
   | 'addProcessorForm.submitButton'
   | 'addProcessorButton'
   | 'addProcessorForm.submitButton'
+  | 'appendValueField.input'
   | 'processorTypeSelector.input'
   | 'fieldNameField.input'
   | 'mockCodeEditor'
diff --git a/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/uri_parts.test.tsx b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/uri_parts.test.tsx
index 573adad3247f5..442788a7f75aa 100644
--- a/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/uri_parts.test.tsx
+++ b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/__jest__/processors/uri_parts.test.tsx
@@ -12,8 +12,6 @@ import { setup, SetupResult, getProcessorValue } from './processor.helpers';
 const defaultUriPartsParameters = {
   keep_original: undefined,
   remove_if_successful: undefined,
-  ignore_failure: undefined,
-  description: undefined,
 };
 
 const URI_PARTS_TYPE = 'uri_parts';
@@ -43,19 +41,22 @@ describe('Processor: URI parts', () => {
       });
     });
     testBed.component.update();
-  });
 
-  test('prevents form submission if required fields are not provided', async () => {
     const {
-      actions: { addProcessor, saveNewProcessor, addProcessorType },
-      form,
+      actions: { addProcessor, addProcessorType },
     } = testBed;
-
-    // Open flyout to add new processor
+    // Open the processor flyout
     addProcessor();
 
     // Add type (the other fields are not visible until a type is selected)
     await addProcessorType(URI_PARTS_TYPE);
+  });
+
+  test('prevents form submission if required fields are not provided', async () => {
+    const {
+      actions: { saveNewProcessor },
+      form,
+    } = testBed;
 
     // Click submit button with only the type defined
     await saveNewProcessor();
@@ -64,16 +65,12 @@ describe('Processor: URI parts', () => {
     expect(form.getErrorsMessages()).toEqual(['A field value is required.']);
   });
 
-  test('saves with default parameter values', async () => {
+  test('saves with required parameter values', async () => {
     const {
-      actions: { addProcessor, saveNewProcessor, addProcessorType },
+      actions: { saveNewProcessor },
       form,
     } = testBed;
 
-    // Open flyout to add new processor
-    addProcessor();
-    // Add type (the other fields are not visible until a type is selected)
-    await addProcessorType(URI_PARTS_TYPE);
     // Add "field" value (required)
     form.setInputValue('fieldNameField.input', 'field_1');
     // Save the field
@@ -88,14 +85,10 @@ describe('Processor: URI parts', () => {
 
   test('allows optional parameters to be set', async () => {
     const {
-      actions: { addProcessor, addProcessorType, saveNewProcessor },
+      actions: { saveNewProcessor },
       form,
     } = testBed;
 
-    // Open flyout to add new processor
-    addProcessor();
-    // Add type (the other fields are not visible until a type is selected)
-    await addProcessorType(URI_PARTS_TYPE);
     // Add "field" value (required)
     form.setInputValue('fieldNameField.input', 'field_1');
 
@@ -109,9 +102,7 @@ describe('Processor: URI parts', () => {
 
     const processors = getProcessorValue(onUpdate, URI_PARTS_TYPE);
     expect(processors[0].uri_parts).toEqual({
-      description: undefined,
       field: 'field_1',
-      ignore_failure: undefined,
       keep_original: false,
       remove_if_successful: true,
       target_field: 'target_field',
diff --git a/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/components/processor_form/processors/append.tsx b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/components/processor_form/processors/append.tsx
index d10347b4d9655..fde39e7462009 100644
--- a/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/components/processor_form/processors/append.tsx
+++ b/x-pack/plugins/ingest_pipelines/public/application/components/pipeline_editor/components/processor_form/processors/append.tsx
@@ -52,7 +52,12 @@ export const Append: FunctionComponent = () => {
         })}
       />
 
-      <UseField config={fieldsConfig.value} component={ComboBoxField} path="fields.value" />
+      <UseField
+        data-test-subj="appendValueField"
+        config={fieldsConfig.value}
+        component={ComboBoxField}
+        path="fields.value"
+      />
     </>
   );
 };