Ignore soft hyphen

Fixes #4961

src/common/InputHandler.test.ts

@@ -619,6 +619,11 @@ describe('InputHandler', () => {
       await inputHandler.parseP('￥￥￥');
       assert.deepEqual(getLines(bufferService, 2), ['￥￥', '￥']);
     });
+    it('should strip soft hyphens (U+00AD)', async () => {
+      await inputHandler.parseP('Soft\xadhy\xadphen');
+      assert.strictEqual(bufferService.buffer.translateBufferLineToString(0, true), 'Softhyphen');
+      assert.strictEqual(bufferService.buffer.x, 10);
+    });
   });
 
   describe('alt screen', () => {

src/common/InputHandler.ts

@@ -533,6 +533,12 @@ export class InputHandler extends Disposable implements IInputHandler {
     for (let pos = start; pos < end; ++pos) {
       code = data[pos];
 
+      // Soft hyphen's (U+00AD) behavior is ambiguous and differs across terminals. We opt to treat
+      // it as a zero-width hint to text layout engines and simply ignore it.
+      if (code === 0xAD) {
+        continue;
+      }
+
       // get charset replacement character
       // charset is only defined for ASCII, therefore we only
       // search for an replacement char if code < 127