• SVGO now requires Node 4 or higher.
• Changed CLI syntax to treat filenames as input, thus allowing svgo *.svg syntax.
• SVGO.optimize() now returns Promise.
• Added datauri option to JS API.
• Added support for SVG 2 href attribute.
• cleanupIDs now don't removes IDs if an image consists only of defs.
• New plugin inlineStyles for converting styles from <style> element to attributes if possible (by @strarsis).
• cleanupNumericValues now rounds values in viewBox (by @caub).
• New plugin: removeScriptElement (disabled by default) to align with removeStyleElement (by @pklingem).
• minifyStyles now removes styles based on usage with controlling options (by @lahmatiy).
• New option except in cleanupIDs to keep IDs (by @Velenir).
• New option force in cleanupIDs to work even if SVG contains style or script elements (by @Velenir).
• Fixed arcs transforming with different signed scale parameters (by @JoshyPHP).
• Fixed removeUselessStrokeAndFill to check for style or script elements per file (by @caub).
• New option keepAriaAttrs in removeUnknownsAndDefaults (by @davidtheclark).
• Corrected parsing in cleanupIDs to account animation syntax (by @caub).
• #ff0000 now converts to red as well as #f00 (by @davidleston).
• Added “gray” variation to colors list per CSS Color Module Level 4 (by @ydaniv).
• Fixed error on empty files.
• A separator character in removeAttrs now can be changed per elemSeparator option (by @mikestreety).
• addAttributesToSVGElement now can add values to attributes.