{"record":{"id":"991a8129cda2bda4","repo":"SeleniumHQ/selenium","slug":"this-browser-does-not-support-federated-credential","errorCode":null,"errorMessage":"This browser does not support Federated Credential Management. Please ensure you're using a supported browser.","messagePattern":"This browser does not support Federated Credential Management\\. Please ensure you're using a supported browser\\.","errorType":"exception","errorClass":"WebDriverException","httpStatus":null,"severity":"error","filePath":"py/selenium/webdriver/remote/webdriver.py","lineNumber":1660,"sourceCode":"            `driver.fedcm.account_list`\n            `driver.fedcm.select_account(0)`\n            `driver.fedcm.accept()`\n            `driver.fedcm.dismiss()`\n            `driver.fedcm.enable_delay()`\n            `driver.fedcm.disable_delay()`\n            `driver.fedcm.reset_cooldown()`\n        \"\"\"\n        return self._fedcm\n\n    @property\n    def supports_fedcm(self) -> bool:\n        \"\"\"Returns whether the browser supports FedCM capabilities.\"\"\"\n        return self.capabilities.get(ArgOptions.FEDCM_CAPABILITY, False)\n\n    def _require_fedcm_support(self) -> None:\n        \"\"\"Raises an exception if FedCM is not supported.\"\"\"\n        if not self.supports_fedcm:\n            raise WebDriverException(\n                \"This browser does not support Federated Credential Management. \"\n                \"Please ensure you're using a supported browser.\"\n            )\n\n    @property\n    def dialog(self) -> Dialog:\n        \"\"\"Returns the FedCM dialog object for interaction.\"\"\"\n        from selenium.webdriver.common.fedcm.dialog import Dialog\n\n        self._require_fedcm_support()\n        return Dialog(self)\n\n    def fedcm_dialog(self, timeout=5, poll_frequency=0.5, ignored_exceptions=None):\n        \"\"\"Waits for and returns the FedCM dialog.\n\n        Args:\n            timeout: How long to wait for the dialog.\n            poll_frequency: How frequently to poll.","sourceCodeStart":1642,"sourceCodeEnd":1678,"githubUrl":"https://github.com/SeleniumHQ/selenium/blob/aa36b38e696a0909e973bdf5e2f9031ffe842c4b/py/selenium/webdriver/remote/webdriver.py#L1642-L1678","documentation":"Raised by _require_fedcm_support() (called by the FedCM dialog/account properties) when the session capabilities do not advertise FedCM support. Selenium gates FedCM (Federated Credential Management) interaction behind a capability (ArgOptions.FEDCM_CAPABILITY) that the browser must accept; if it is absent/false, the FedCM dialog API is unavailable.","triggerScenarios":"Accessing driver.dialog (or any property that calls _require_fedcm_support()) on a session whose capabilities do not have the FedCM capability set to True. The check is `not self.capabilities.get(ArgOptions.FEDCM_CAPABILITY, False)`.","commonSituations":"Using a browser/version that does not support FedCM, or forgetting to enable the FedCM capability at session creation. FedCM support is browser-dependent (recent Chrome versions).","solutions":["Enable the FedCM capability at session creation: options.enableFedCm = True (or set_capability with ArgOptions.FEDCM_CAPABILITY).","Use a recent Chrome/Chromium build that supports FedCM.","Check driver.supports_fedcm before touching driver.dialog or driver.fedcm methods."],"exampleFix":"# before\noptions = webdriver.ChromeOptions()\ndriver = webdriver.Chrome(options=options)\ndriver.dialog  # raises\n\n# after\noptions = webdriver.ChromeOptions()\noptions.enableFedCm = True\ndriver = webdriver.Chrome(options=options)\ndriver.dialog  # works","handlingStrategy":"validation","validationCode":"if not driver.supports_fedcm:\n    raise RuntimeError('Enable FedCM: options.enableFedCm = True, use a supported browser')\ndriver.dialog","typeGuard":"def fedcm_supported(driver) -> bool:\n    return bool(driver.supports_fedcm)","tryCatchPattern":"from selenium.common.exceptions import WebDriverException\ntry:\n    driver.dialog\nexcept WebDriverException:\n    # skip FedCM interaction; browser/capability unsupported\n    pass","preventionTips":["Set options.enableFedCm = True at session creation.","Use a recent Chromium that supports FedCM.","Check driver.supports_fedcm before FedCM interactions."],"tags":["fedcm","capabilities","authentication","browser-support"],"backgroundTag":null,"analyzedSha":"aa36b38e696a0909e973bdf5e2f9031ffe842c4b","analyzedAt":"2026-08-14T02:32:32.244Z","schemaVersion":2},"datasetVersion":"2026-08-14T05:17:29.042Z"}