{"record":{"id":"0dd162ff9a5fddde","repo":"dgtlmoon/changedetection.io","slug":"error-connecting-to-the-browser-check-your-browse","errorCode":null,"errorMessage":"Error connecting to the browser, check your browser connection address (should be ws:// or wss://","messagePattern":"Error connecting to the browser, check your browser connection address \\(should be ws:// or wss://","errorType":"exception","errorClass":"BrowserConnectError","httpStatus":null,"severity":"error","filePath":"changedetectionio/content_fetchers/puppeteer.py","lineNumber":301,"sourceCode":"        extra_wait = min(n, 15)\n\n        logger.debug(f\"Extra wait set to {extra_wait}s, requested was {n}s.\")\n\n        from pyppeteer import Pyppeteer\n        pyppeteer_instance = Pyppeteer()\n\n        # Connect directly using the specified browser_ws_endpoint\n        # @todo timeout\n        try:\n            logger.debug(f\"[{watch_uuid}] Connecting to browser at {self.browser_connection_url}\")\n            self.browser = await pyppeteer_instance.connect(browserWSEndpoint=self.browser_connection_url,\n                                                            ignoreHTTPSErrors=True\n                                                            )\n            logger.debug(f\"[{watch_uuid}] Browser connected successfully\")\n        except websockets.exceptions.InvalidStatusCode as e:\n            raise BrowserConnectError(msg=f\"Error while trying to connect the browser, Code {e.status_code} (check your access, whitelist IP, password etc)\")\n        except websockets.exceptions.InvalidURI:\n            raise BrowserConnectError(msg=f\"Error connecting to the browser, check your browser connection address (should be ws:// or wss://\")\n        except Exception as e:\n            raise BrowserConnectError(msg=f\"Error connecting to the browser - Exception '{str(e)}'\")\n\n        # more reliable is to just request a new page\n        try:\n            logger.debug(f\"[{watch_uuid}] Creating new page\")\n            self.page = await self.browser.newPage()\n            logger.debug(f\"[{watch_uuid}] Page created successfully\")\n        except Exception as e:\n            logger.error(f\"[{watch_uuid}] Failed to create new page: {e}\")\n            # Browser is connected but page creation failed - must cleanup browser\n            try:\n                await asyncio.wait_for(self.browser.close(), timeout=3.0)\n            except Exception as cleanup_error:\n                logger.error(f\"[{watch_uuid}] Failed to cleanup browser after page creation failure: {cleanup_error}\")\n            finally:\n                self.browser = None\n            raise","sourceCodeStart":283,"sourceCodeEnd":319,"githubUrl":"https://github.com/dgtlmoon/changedetection.io/blob/5d9c7c6da76340597243e8163c4f2439237fa0e8/changedetectionio/content_fetchers/puppeteer.py#L283-L319","documentation":"BrowserConnectError raised when pyppeteer's websocket endpoint URL fails to parse as a valid ws:// or wss:// URI (websockets.exceptions.InvalidURI).","triggerScenarios":"browser_connection_url missing the ws:// scheme (e.g. 'localhost:3000' or 'http://host'), malformed URI, or trailing garbage that breaks parsing.","commonSituations":"Copy-pasting an http:// URL into the puppeteer connection setting; missing scheme entirely after env var misconfiguration.","solutions":["Set the URL with an explicit scheme: ws://host:port or wss://host:port","Check the environment/config value actually loaded (no stray quotes/whitespace)"],"exampleFix":"# before\nhttp://chrome:3000\n# after\nws://chrome:3000","handlingStrategy":"validation","validationCode":"from urllib.parse import urlparse\ndef valid_ws_url(u: str) -> bool:\n    p = urlparse(u)\n    return p.scheme in ('ws', 'wss') and bool(p.hostname)","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Always configure ws:// or wss:// scheme explicitly","Normalize browser URLs in config management, not ad-hoc env edits"],"tags":["websocket","puppeteer","invalid-url"],"backgroundTag":"invalid-websocket-url","analyzedSha":"5d9c7c6da76340597243e8163c4f2439237fa0e8","analyzedAt":"2026-08-27T19:41:16.067Z","schemaVersion":2},"datasetVersion":"2026-08-28T00:17:15.603Z"}