Added

• Ferrum::Network::Exchange#blob? determines if the exchange is blob [#516]
• Ferrum::Network::Request#headers are enhanced and supplemented with Network.requestWillBeSentExtraInfo [#506]
• Ferrum::Page#off to unsubscribe from CDP events [#455]
• Ferrum::Mouse#scroll_by to be able to scroll by, as alternative to scroll_to [#514]
• Ferrum::Network::Exchange#unknown determines if the exchange is in an unknown state, meaning that browser might not return info about it [#426]
• Ferrum::Network::Exchange#loader_id returns loader id [#426]
• Ferrum::Browser#debug opens headless session in the browser devtools frontend [#519]
• Ferrum::Frame#parent returns the parent frame if this frame is nested [#523]
• Ferrum::Frame#frame_element returns the element in which the window is embedded [#524]
• Ferrum::Page#start_screencast starts sending frames to record screencast [#494]
• Ferrum::Page#stop_screencast stops sending frames [#494]
• Ferrum::Browser#new(incognito: false) whether to create an incognito profile for the browser startup window, true by default.

Changed

• Ferrum::Network::Exchange#finished? takes into account that exchange might be in an unknown state after loader changed(next go_to call) and considers such as finished [#426]
• headless: "new" mode is removed as it's now default in modern Chrome, just use headless: true instead [#518]

Fixed

• Correctly set mouse events buttons property [#509]
• Prevent 'Hash#[]=': can't add a new key into hash during iteration [#513]
• Ferrum::Network::Exchange#finished? and Ferrum::Network#wait_for_idle take into account that request can be a blob [#496]
• Safe call body method (DOM) when page is empty and no html [#522]