diff --git a/css/xterm.css b/css/xterm.css
index 4e1aad14..ac8cd45b 100644
--- a/css/xterm.css
+++ b/css/xterm.css
@@ -174,7 +174,7 @@
     text-decoration: line-through;
 }
 
-.xterm-screen canvas .xterm-decoration {
+#terminal-container > div > div.xterm-screen > div.xterm-decoration {
 	z-index: 6;
 	position: absolute;
 }
diff --git a/demo/client.ts b/demo/client.ts
index 0ca4d4bf..193b78b0 100644
--- a/demo/client.ts
+++ b/demo/client.ts
@@ -531,5 +531,4 @@ function decoration() {
   const marker = term.addMarker(1);
   const decoration = term.registerDecoration({ marker });
   decoration.element.style.backgroundColor = 'red';
-  decoration.element.style.position = 'absolute';
-}
+}
\ No newline at end of file
diff --git a/test/api/Terminal.api.ts b/test/api/Terminal.api.ts
index 1fe75456..c10094ca 100644
--- a/test/api/Terminal.api.ts
+++ b/test/api/Terminal.api.ts
@@ -731,6 +731,28 @@ describe('API Integration Tests', function(): void {
     await pollFor(page, `window.term._core._renderService.dimensions.actualCellWidth > 0`, true);
   });
 
+  describe.only('registerDecoration', () => {
+    it('should register a decoration', async () => {
+      await openTerminal(page);
+      await page.evaluate(`window.marker = window.term.addMarker(1)`);
+      await page.evaluate(`window.decoration = window.term.registerDecoration({ marker: window.marker });`);
+      assert.notEqual(await page.evaluate(`document.querySelector('.xterm-screen .xterm-decoration')`), undefined);
+    });
+    it('should return undefined when the marker has already been disposed of', async () => {
+      await openTerminal(page);
+      await page.evaluate(`window.marker = window.term.addMarker(1)`);
+      await page.evaluate(`window.marker.dispose()`);
+      assert.equal(await page.evaluate(`window.decoration = window.term.registerDecoration({ marker: window.marker });`), undefined);
+      assert.equal(await page.evaluate(`document.querySelector('.xterm-screen .xterm-decoration')`), undefined);
+    });
+    it.skip('should throw when a negative x offset is provided', async () => {
+      await openTerminal(page);
+      await page.evaluate(`window.marker = window.term.addMarker(1)`);
+      assert.throws(async () => await page.evaluate(`window.decoration = window.term.registerDecoration({ marker: window.marker, x: -2 });`));
+      assert.equal(await page.evaluate(`document.querySelector('.xterm-screen .xterm-decoration')`), undefined);
+    });
+  });
+
   describe('registerLinkProvider', () => {
     it('should fire provideLinks when hovering cells', async () => {
       await openTerminal(page, { rendererType: 'dom' });