Subscribe to WebDriver BiDi's console/log module during a Selenium BiDi session to capture browser console messages and JavaScript errors as they occur
domain: selenium.dev · 6 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Enable BiDi in the browser Options for your language binding first, since BiDi is not on by default in Selenium
Access logging via the driver's script namespace, e.g. in Python: driver.script.add_console_message_handler(handler_function)
The registered handler receives entries corresponding to the underlying BiDi log.entryAdded event, exposing fields like text and timestamp
Register a separate handler for uncaught JavaScript errors, e.g. driver.script.add_javascript_error_handler(...), which adds a stack-trace field
Store the ID returned by the add_* call so the handler can be removed later via the matching remove_* call
Trigger the page interaction, then wait for the collected list to populate, since delivery is asynchronous
Known gotchas
The underlying spec event is named log.entryAdded, but Selenium wraps it under the script namespace/BiDi logging API rather than exposing a top-level 'Log' object
Not all language bindings implement these handler wrappers to the same degree — check the per-language docs before assuming parity across Java/Python/Ruby/JS/.NET
Handlers only capture messages logged after registration and must be explicitly removed by their stored ID; there is no automatic expiry
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