diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index 8df3ca7f..2119bfad 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -11,6 +11,10 @@ permissions:
 
 jobs:
   release:
+    # Releases are cut from the upstream repository only. Without this guard the
+    # workflow also runs on forks, where semantic-release rewrites the version in
+    # pyproject.toml, commits to the default branch and attempts a PyPI upload.
+    if: github.repository == 'appium/python-client'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v7
diff --git a/appium/options/common/base.py b/appium/options/common/base.py
index 5bd4f1a9..2de5a5f9 100644
--- a/appium/options/common/base.py
+++ b/appium/options/common/base.py
@@ -109,7 +109,7 @@ def process_key(k: str) -> str:
                 return key
             return key if ':' in key else f'{APPIUM_PREFIX}{key}'
 
-        processed_caps = {process_key(k): v for k, v in copy.deepcopy(capabilities).items()}
+        processed_caps = {process_key(k): v for k, v in capabilities.items()}
         return {'capabilities': {'firstMatch': [{}], 'alwaysMatch': processed_caps}}
 
     def to_w3c(self) -> dict:
diff --git a/test/unit/options/options_test.py b/test/unit/options/options_test.py
new file mode 100644
index 00000000..6692eb9a
--- /dev/null
+++ b/test/unit/options/options_test.py
@@ -0,0 +1,27 @@
+from appium.options.common.base import AppiumOptions
+
+
+def test_as_w3c():
+    caps = {
+        'platformName': 'Android',
+        'platformVersion': '11.0',
+        'deviceName': 'Android Emulator',
+        'automationName': 'UiAutomator2',
+        'app': '/path/to/app.apk',
+        'customCap': 'customValue',
+    }
+    res = AppiumOptions.as_w3c(caps)
+    expected = {
+        'capabilities': {
+            'firstMatch': [{}],
+            'alwaysMatch': {
+                'platformName': 'Android',
+                'appium:platformVersion': '11.0',
+                'appium:deviceName': 'Android Emulator',
+                'appium:automationName': 'UiAutomator2',
+                'appium:app': '/path/to/app.apk',
+                'appium:customCap': 'customValue',
+            },
+        }
+    }
+    assert res == expected