Preferences

There are a couple of preferences associated with the Remote Agent:

Configurable preferences

remote.active-protocols

Defines the remote protocols that are active. Available protocols are, WebDriver BiDi (1), and CDP (2). Multiple protocols can be activated at the same time by using bitwise or with the values, such as 3 for both protocols. Defaults to 1 (WebDriver BiDi) since Firefox 129.

remote.events.async.enabled (experimental)

This preference determines whether asynchronous event dispatching is used to simulate real user input. By default, it is set to false, meaning events are synthesized directly in the web page’s content process, bypassing OS-level layers like APZ (asynchronous panning and zooming).

Warning: This feature is still under development and should only be enabled for testing purposes, not in production environments.

remote.experimental.enabled

Defines if WebDriver BiDi experimental commands and events are available for usage. Defaults to true in Nightly builds, and false otherwise.

remote.log.level

Defines the verbosity of the internal logger. Available levels are, in descending order of severity, Trace, Debug, Config, Info, Warn, Error, and Fatal. Note that the value is treated case-sensitively.

remote.log.truncate

Defines whether long log messages should be truncated. Defaults to true.

remote.prefs.recommended

By default remote protocols attempts to set a range of preferences deemed suitable in automation when it starts. These include the likes of disabling auto-updates, Telemetry, and first-run UX. Set this preference to false to skip setting those preferences, which is mostly useful for internal Firefox CI suites.

The user preference file takes precedence over the recommended preferences, meaning any user-defined preference value will not be overridden.

remote.retry-on-abort

This preference defines whether certain IPC calls from the parent process to content processes should be retried when a browsing context is replaced due to cross-origin navigation, or made inactive when a page moved into BFCache.

Introduced in Firefox 132, the preference is set to true by default.