fix Debug console stop listening output

fixes #83906

src/vs/workbench/contrib/debug/common/replModel.ts

@@ -10,7 +10,7 @@ import { ExpressionContainer } from 'vs/workbench/contrib/debug/common/debugMode
 import { isString, isUndefinedOrNull, isObject } from 'vs/base/common/types';
 import { basenameOrAuthority } from 'vs/base/common/resources';
 import { URI } from 'vs/base/common/uri';
-import { endsWith } from 'vs/base/common/strings';
+import { endsWith, startsWith } from 'vs/base/common/strings';
 import { generateUuid } from 'vs/base/common/uuid';
 import { Emitter } from 'vs/base/common/event';
 
@@ -134,8 +134,9 @@ export class ReplModel {
 
 		if (typeof data === 'string') {
 			const previousElement = this.replElements.length ? this.replElements[this.replElements.length - 1] : undefined;
-			if (previousElement instanceof SimpleReplElement && previousElement.severity === sev && !endsWith(previousElement.value, '\n') && !endsWith(previousElement.value, '\r\n')) {
+			if (!startsWith(data, '\n') && previousElement instanceof SimpleReplElement && previousElement.severity === sev && !endsWith(previousElement.value, '\n') && !endsWith(previousElement.value, '\r\n')) {
 				previousElement.value += data;
+				this._onDidChangeElements.fire();
 			} else {
 				const element = new SimpleReplElement(session, `topReplElement:${topReplElementCounter++}`, data, sev, source);
 				this.addReplElement(element);

src/vs/workbench/contrib/debug/test/browser/debugModel.test.ts

@@ -498,11 +498,13 @@ suite('Debug - Model', () => {
 		repl.appendToRepl(session, '3\n4', severity.Info);
 		repl.appendToRepl(session, '5\n', severity.Info);
 		repl.appendToRepl(session, '6', severity.Info);
+		repl.appendToRepl(session, '\n7', severity.Info);
 		elements = <SimpleReplElement[]>repl.getReplElements();
-		assert.equal(elements.length, 3);
+		assert.equal(elements.length, 4);
 		assert.equal(elements[0], '1\n');
 		assert.equal(elements[1], '23\n45\n');
 		assert.equal(elements[2], '6');
+		assert.equal(elements[3], '\n7');
 	});
 
 	test('repl merging', () => {