• Remove d3-request; add d3-fetch.
• Remove d3-queue; see Promise.all.
• Add d3-scale-chromatic.
• Add d3-contour.
• Add selection.clone.
• Add d3.create.
• Add projection.angle.
• Remove d3.schemeCategory20* categorical color schemes. (See note below.)
• Fix duplicate installation of D3 modules at different versions. (#3256)
• Fix d3.format’s SI format for locales with currency suffixes.

D3 now includes new categorical color schemes from ColorBrewer, along with ColorBrewer’s excellent diverging, sequential single-hue and sequential multi-hue color schemes. The twenty-color schemes were removed because their grouped design often falsely implied non-existent relationships in the data: a shared hue can imply that the encoded data are part of a group (a super-category), while the relative lightness can falsely imply order.

For more on what’s new, read CHANGES.