future_changes.md

[4.10.0] - 2026-05-dd

Added

• ggdeck() — a new function for overlaying multiple independent plots in a single unified view.

  In a typical scenario, one axis is shared by all plots in the deck, enabling dual-axis effects and multivariate comparisons.

  See examples:

  • dual-axis effect
  • multivariate comparison

• Datetime: %f formatting pattern — support for milliseconds when formatting datetime values, zero-padded to 3 digits [#1482].

  See: example notebook.

• In legends:

  • override_aes in guide_legend() can now customize filled 2D legend keys:

    • size controls the key border width;
    • width and height control the relative key size.

    See: example notebook.

• Indication of removed records [LPK-81], [#686].

  When records in data are dropped by active sampling or because they contain missing or out-of-bounds values, the user is now informed of the number of dropped records and the reason they were dropped.

  The new na_rm parameter in geom_xxx() and stat_xxx() functions controls the display of such messages:

  • na_rm=false (default) — records are removed and messages are shown;
  • na_rm=true — records are removed silently.

  See: example notebook.

• Alpha (transparency) component:

  • Hex colors accept #RRGGBBAA or #RGBA notation.
  • Colors accept an opacity suffix in the form "named color / opacity", for example "steelblue / 0.35".

  See: example notebook.

• In geom_imshow(), new parameters for controlling the colorbar breaks and labels [#1486]:

  • breaks, labels, lablim, format

• Memo for Kotlin API users:

  • Added WasmJS support [LPK-296], [LPC-52].

Changed

Fixed

• Add 'synchronized tooltips' feature [#1415].
• Alpha is not supported in element_text() [#1462].
• geom_imshow(): should render transparency for NaNs when all other pixel values are identical [#1485].
• scale_alpha: conflict of constant and mapped values of alpha aesthetic [#706].