diff --git a/core/misc/cspell/dictionary.txt b/core/misc/cspell/dictionary.txt
index 55be59f852..d060172c89 100644
--- a/core/misc/cspell/dictionary.txt
+++ b/core/misc/cspell/dictionary.txt
@@ -1101,6 +1101,7 @@ someschema
 somethinggeneric
 sortablejs
 sourcedir
+sourceediting
 spacebar
 spagna
 specialchars
diff --git a/core/modules/ckeditor5/tests/src/Nightwatch/Tests/ckEditor5EditorHeightTest.js b/core/modules/ckeditor5/tests/src/Nightwatch/Tests/ckEditor5EditorHeightTest.js
new file mode 100644
index 0000000000..4c2be7676a
--- /dev/null
+++ b/core/modules/ckeditor5/tests/src/Nightwatch/Tests/ckEditor5EditorHeightTest.js
@@ -0,0 +1,172 @@
+module.exports = {
+  '@tags': ['core', 'ckeditor5'],
+  before(browser) {
+    browser.drupalInstall({ installProfile: 'minimal' });
+  },
+  after(browser) {
+    browser.drupalUninstall();
+  },
+  'Test page': (browser) => {
+    browser.drupalLoginAsAdmin(() => {
+      browser
+        // Enable required modules.
+        .drupalRelativeURL('/admin/modules')
+        .click('[name="modules[ckeditor5][enable]"]')
+        .click('[name="modules[field_ui][enable]"]')
+        .submitForm('input[type="submit"]') // Submit module form.
+        .waitForElementVisible(
+          '.system-modules-confirm-form input[value="Continue"]',
+        )
+        .submitForm('input[value="Continue"]') // Confirm installation of dependencies.
+        .waitForElementVisible('.system-modules', 10000)
+
+        // Create new input format.
+        .drupalRelativeURL('/admin/config/content/formats/add')
+        .waitForElementVisible('body')
+        .updateValue('[data-drupal-selector="edit-name"]', 'test')
+        .pause(500) // Wait for machine name to update.
+        .click(
+          '[data-drupal-selector="edit-editor-editor"] option[value=ckeditor5]',
+        )
+        .waitForElementVisible(
+          '[data-drupal-selector="edit-editor-settings-toolbar"]',
+        ) // Wait for Ck5 settings to be visible.
+        .click('.ckeditor5-toolbar-button-sourceEditing') // Select the Source Editing button.
+        .keys(browser.Keys.DOWN) // Hit the down arrow key to move it to the toolbar.
+        .waitForElementVisible(
+          '[href*=edit-editor-settings-plugins-ckeditor5-sourceediting]',
+        ) // Wait for new source editing vertical tab to be present before continuing.
+        .submitForm('input[type="submit"]')
+        .waitForElementVisible('[data-drupal-messages]')
+        .assert.textContains('[data-drupal-messages]', 'Added text format')
+
+        // Create new content type.
+        .drupalRelativeURL('/admin/structure/types/add')
+        .waitForElementVisible('body')
+        .updateValue('[data-drupal-selector="edit-name"]', 'test')
+        .pause(500) // Wait for machine name to update.
+        .submitForm('input[type="submit"]')
+        .waitForElementVisible('[data-drupal-messages]')
+        .assert.textContains(
+          '[data-drupal-messages]',
+          'The content type test has been added',
+        )
+
+        // Navigate to the create content page and measure height of the editor.
+        .drupalRelativeURL('/node/add/test')
+        .waitForElementVisible('.ck-editor__editable')
+        .execute(
+          // eslint-disable-next-line func-names, prefer-arrow-callback, no-shadow
+          function () {
+            const height = document.querySelector(
+              '.ck-editor__editable',
+            ).clientHeight;
+
+            // We expect height to be 320, but test to ensure that it's greater
+            // than 300. We want to ensure that we don't hard code a very specific
+            // value because tests might break if styles change (line-height, etc).
+            // Note that the default height for CKEditor5 is 47.
+            return height > 300;
+          },
+          [],
+          (result) => {
+            browser.assert.ok(
+              result.value,
+              'Editor height is set to 9 rows (default).',
+            );
+          },
+        )
+        .click('.ck-source-editing-button')
+        .waitForElementVisible('.ck-source-editing-area')
+        .execute(
+          // eslint-disable-next-line func-names, prefer-arrow-callback, no-shadow
+          function () {
+            const height = document.querySelector(
+              '.ck-source-editing-area',
+            ).clientHeight;
+
+            // We expect height to be 320, but test to ensure that it's greater
+            // than 300. We want to ensure that we don't hard code a very specific
+            // value because tests might break if styles change (line-height, etc).
+            // Note that the default height for CKEditor5 is 47px.
+            return height > 300;
+          },
+          [],
+          (result) => {
+            browser.assert.ok(
+              result.value,
+              'Source editing height is set to 9 rows (default).',
+            );
+          },
+        )
+
+        // Double the editor row count.
+        .drupalRelativeURL('/admin/structure/types/manage/test/form-display')
+        .waitForElementVisible('body')
+        .click('[data-drupal-selector="edit-fields-body-settings-edit"]')
+        .waitForElementVisible(
+          '[data-drupal-selector="edit-fields-body-settings-edit-form-settings-rows"]',
+        )
+        .updateValue(
+          '[data-drupal-selector="edit-fields-body-settings-edit-form-settings-rows"]',
+          '18',
+        )
+        .click(
+          '[data-drupal-selector="edit-fields-body-settings-edit-form-actions-save-settings"]',
+        ) // Save field settings.
+        .waitForElementVisible(
+          '[data-drupal-selector="edit-fields-body"] .field-plugin-summary',
+        )
+        .click('[data-drupal-selector="edit-submit"]')
+        .waitForElementVisible('[data-drupal-messages]')
+        .assert.textContains(
+          '[data-drupal-messages]',
+          'Your settings have been saved',
+        )
+
+        // Navigate to the create content page and measure height of the editor.
+        .drupalRelativeURL('/node/add/test')
+        .execute(
+          // eslint-disable-next-line func-names, prefer-arrow-callback, no-shadow
+          function () {
+            const height = document.querySelector(
+              '.ck-editor__editable',
+            ).clientHeight;
+
+            // We expect height to be 640, but test to ensure that it's greater
+            // than 600. We want to ensure that we don't hard code a very specific
+            // value because tests might break if styles change (line-height, etc).
+            // Note that the default height for CKEditor5 is 47px.
+            return height > 600;
+          },
+          [],
+          (result) => {
+            browser.assert.ok(result.value, 'Editor height is set to 18 rows.');
+          },
+        )
+        .click('.ck-source-editing-button')
+        .waitForElementVisible('.ck-source-editing-area')
+        .execute(
+          // eslint-disable-next-line func-names, prefer-arrow-callback, no-shadow
+          function () {
+            const height = document.querySelector(
+              '.ck-source-editing-area',
+            ).clientHeight;
+
+            // We expect height to be 640, but test to ensure that it's greater
+            // than 600. We want to ensure that we don't hard code a very specific
+            // value because tests might break if styles change (line-height, etc).
+            // Note that the default height for CKEditor5 is 47.
+            return height > 600;
+          },
+          [],
+          (result) => {
+            browser.assert.ok(
+              result.value,
+              'Source editing height is set to 18 rows (default).',
+            );
+          },
+        );
+    });
+  },
+};