Bug 1995452 - add a desktop-only UA override for polymarket.com; r=webcompat-reviewers,ksenia

Differential Revision: https://phabricator.services.mozilla.com/D269472

Author: wisniewskit

browser/extensions/webcompat/data/interventions.json

@@ -5674,5 +5674,22 @@
         }
       }
     ]
+  },
+  "1995452": {
+    "label": "polymarket.com",
+    "bugs": {
+      "1995452": {
+        "issue": "extra-scrollbars",
+        "matches": ["*://polymarket.com/*"]
+      }
+    },
+    "interventions": [
+      {
+        "platforms": ["desktop"],
+        "content_scripts": {
+          "css": ["1995452-polymarket.com-hide-scrollbars.css"]
+        }
+      }
+    ]
   }
 }

browser/extensions/webcompat/injections/css/1995452-polymarket.com-hide-scrollbars.css

@@ -0,0 +1,14 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * polymarket.com - extra scrollbars are visible
+ * Bug #1995452 - https://bugzilla.mozilla.org/show_bug.cgi?id=1995452
+ *
+ * The site uses non-standard webkit-scrollbar CSS to hide scrollbars.
+ * We can use the web standards compliant method to hide them instead.
+ */
+* {
+  scrollbar-width: none;
+}

testing/webcompat/interventions/tests/test_1995452_polymarket_com.py

@@ -0,0 +1,33 @@
+import pytest
+
+URL = "https://polymarket.com/sports/live"
+
+CONTAINER_CSS = "#scoreboard-scroll-container"
+
+
+async def is_scrollbar_visible(client):
+    await client.navigate(URL)
+    container = client.await_css(CONTAINER_CSS)
+    return client.execute_script(
+        """
+      const container = arguments[0];
+      return Math.round(container.getBoundingClientRect().height) != container.clientHeight;
+    """,
+        container,
+    )
+
+
+@pytest.mark.skip_platforms("android")
+@pytest.mark.need_visible_scrollbars
+@pytest.mark.asyncio
+@pytest.mark.with_interventions
+async def test_enabled(client):
+    assert not await is_scrollbar_visible(client)
+
+
+@pytest.mark.skip_platforms("android")
+@pytest.mark.need_visible_scrollbars
+@pytest.mark.asyncio
+@pytest.mark.without_interventions
+async def test_disabled(client):
+    assert await is_scrollbar_visible(client)