Added

• Introduced continous integration builds for Linux- and Windows 32-bit binaries
• Added commands for setting- and getting the window position
• Added new extension commands for finding an element’s anonymous children and querying its attributes; accessible through the /session/{sessionId}/moz/xbl/{elementId}/anonymous_children to return all anonymous children and /session/{sessionId}/moz/xbl/{elementId}/anonymous_by_attribute to return an anonymous element by a name and attribute query
• Introduced a moz:firefoxOptions capability to customise a Firefox session:
  • The binary, args, and profile entries on this dictionary is equivalent to the old firefox_binary, firefox_args, and firefox_profile capabilities, which have now all been removed
  • The log capability takes a dictionary such as {log: "trace"} to enable trace level verbosity in Gecko
  • The prefs capability lets you define Firefox preferences through capabilities
• Re-introduced the --webdriver-port argument as a hidden alias to --port

Changed

• firefox_binary, firefox_args, and firefox_profile capabilities removed in favour of the moz:firefoxOptions dictionary detailed above and in the README
• Removed --no-e10s flag, and geckodriver will from now rely on the Firefox default multiprocessing settings (override using preferences)
• Disable pop-up blocker in the default profile by @juangj
• Changed Rust compiler version to 1.12 (beta) temporarily because of trouble linking Musl binaries
• Replaced env_logger logging facility with the slog package, causing the RUST_LOG environment variable to no longer have any affect
• Updated the WebDriver Rust library to version 0.15.

Fixed

• Corrected link to repository in Cargo metadata
• Verbosity shorthand flag -v[v] now works again, following the replacement of the argument parsing library in the previous release
• When the HTTPD fails to start, errors are propagated to the user
• Disabled the additional welcome URL (startup.homepage_welcome_url.additional) so that officially branded Firefox builds do not start with two open tabs in fresh profiles
• Disabled homepage override URL redirection on milestone upgrades, which means a tab with an upgrade notice is not displayed when launching a new Firefox version