plotly · emilykl · Aug 25, 2026 · Aug 24, 2026 · Aug 24, 2026 · Aug 24, 2026
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -7,38 +7,42 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ### Fixed
 - Improve `px.*_map()` auto-fitting behavior when `zoom` and `center` are not specified [[#5686](https://github.com/plotly/plotly.py/pull/5686)]
 
+### Updated
+- Update plotly.js from version 3.6.0 to version 4.0.0 [[#5673](https://github.com/plotly/plotly.py/pull/5673)]. This is a major-version release with many changes. See the [plotly.js release notes](https://github.com/plotly/plotly.js/releases/tag/v4.0.0) for the full list. The most significant changes include:
+  - Add `quiver` trace type to visualize vector fields using arrows [[#7710](https://github.com/plotly/plotly.js/pull/7710), [#7945](https://github.com/plotly/plotly.js/issues/7945)]
+  - Add "Share Chart" modebar button for generating a chart-sharing link via Plotly Cloud [[#7909](https://github.com/plotly/plotly.js/pull/7909)]
+  - Remove `scattermapbox`, `choroplethmapbox`, `densitymapbox` trace types, the `mapbox` subplot, and the `mapboxAccessToken` config option [[#7860](https://github.com/plotly/plotly.js/pull/7860)]. Use the equivalent `*map` traces instead.
+    - The corresponding `graph_objects` and Plotly Express functions have also been removed in plotly.py; use the `map` versions instead
+  - Drop support for MathJax v2, and add support for v4 [[#7898](https://github.com/plotly/plotly.js/pull/7898)]. MathJax is the JavaScript library used for rendering mathematical equations in plotly charts.
+  - Switch color processing library from [TinyColor](https://github.com/bgrins/TinyColor) to [culori](https://culorijs.org) [[#7536](https://github.com/plotly/plotly.js/pull/7536), [#7962](https://github.com/plotly/plotly.js/pull/7962)]. There are some changes to supported color string formats as a result:
+    - `rgb()`/`rgba()` strings with decimal 0–1 fractions are no longer supported
+    - `hsv()` color strings are no longer supported
+    - Strings with invalid syntax such as `hsl(120, 50% 50%)` are no longer supported
+    - New supported formats: `'#ff0000aa'`, `'#f00a'`, `'rgb(255 0 0)'`, `'rgba(255 0 0 / 0.5)'`, `'hsl(0 100% 50% / 0.5)'`, `'hsla(0, 100%, 50%, 0.5)'`, `'hwb(0, 0%, 0%)'`, `lab()`, `lch()`, `oklab()`, `oklch()`, `color()`, `hsl(0.5turn 60% 40%)`, `hsl(none 60% 40%)`
+  - Replace `country-regex` with `country-iso-search` to search for country names in choropleth, scattergeo traces [[#7856](https://github.com/plotly/plotly.js/pull/7856)]. Most country names are handled exactly the same; a small number of legacy entries have been removed.
+  - Change `layout.geo.fitbounds` default from `false` to `'locations'` [[#7895](https://github.com/plotly/plotly.js/pull/7895)]. `geo` subplots will now auto-fit the initial view to the trace data by default.
+  - Dynamically compute `center` and `zoom` values for `scattermap` and `densitymap` traces. The initial map view will now auto-fit to the trace data by default. Add `layout.map.fitbounds` attribute (default `'locations'`) to enable or disable auto-fitting behavior [[#7884](https://github.com/plotly/plotly.js/pull/7884), [#7913](https://github.com/plotly/plotly.js/pull/7913)]
+  - Fix GeoJSON bounding-box computation for `choropleth` and `scattergeo` traces whose geometry crosses the antimeridian [[#7891](https://github.com/plotly/plotly.js/pull/7891)]
 
-## [7.0.0rc0] - 2026-07-29
 
-### Removed
-- Remove the deprecated Figure Factory functions `create_2d_density`, `create_annotated_heatmap`, `create_bullet`, `create_candlestick`, `create_choropleth`, `create_distplot`, `create_facet_grid`, `create_gantt`, `create_hexbin_mapbox`, `create_ohlc`, `create_scatterplotmatrix`, and `create_violin` [[#5627](https://github.com/plotly/plotly.py/pull/5627)]
-- Remove support for Kaleido versions less than v1.0.0 for static image generation [[#5677](https://github.com/plotly/plotly.py/pull/5677)]
-- Remove support for Orca for static image generation [[#5677](https://github.com/plotly/plotly.py/pull/5677)]
-- Remove `engine` argument from functions `fig.write_image()`,`fig.to_image()`, `pio.write_image()`, `pio.write_images()`, `pio.to_image()`, `pio.full_figure_for_development()`, and from renderer constructors [[#5677](https://github.com/plotly/plotly.py/pull/5677)]
+
+## [7.0.0rc0] - 2026-07-29
 
 ### Fixed
 - Fix `hex_to_rgb` parsing of 3-digit shorthand hexadecimal colors such as `#FFF` [[#5662](https://github.com/plotly/plotly.py/pull/5662)], with thanks to @genrichez for the contribution!
 - Add `<!doctype html>` to the `to_html()` template to comply with modern web standards [[#5693](https://github.com/plotly/plotly.py/pull/5693)], with thanks to @mishrakushal for the contribution!
 - Apply `histfunc`/`z` aggregation to `marginal_x`/`marginal_y="histogram"` subplots in `density_heatmap`/`density_contour`, instead of always showing raw bin counts [[#3521](https://github.com/plotly/plotly.py/issues/3521)], with thanks to @lucasjamar for the contribution!
 - Fix `mpl_to_plotly` silently dropping matplotlib path collections in data coordinates (such as violin plots, pcolor, event plots, stack plots, fill_between, and stem plots) by rendering them as filled polygons or lines [[#5702](https://github.com/plotly/plotly.py/pull/5702)], with thanks to @robertoffmoura for the contribution!
 
-
-## [6.9.0] - 2026-07-09
-
-### Fixed
-- Raise a clear `ValueError` when an unsupported marginal plot type is passed to Plotly Express, instead of failing later with a cryptic `'NoneType' object has no attribute 'constructor'` message [[#5625](https://github.com/plotly/plotly.py/pull/5625)], with thanks to @eugen-goebel for the contribution!
-- Read and write figure JSON files as UTF-8 in `read_json`/`write_json` so figures containing non-ASCII text are handled correctly on platforms whose default encoding is not UTF-8 (e.g. cp1252 on Windows) [[#5633](https://github.com/plotly/plotly.py/pull/5633)]
-
-
-### Updated
-- Update plotly.js from version 3.6.0 to version 3.7.0. See the plotly.js [release notes](https://github.com/plotly/plotly.js/releases/tag/v3.7.0) for more information [[#5639](https://github.com/plotly/plotly.py/pull/5639)]. Notable changes include:
-  - Rename `sendDataToCloud` modebar button to `sendChartToCloud`, and update to upload chart to Plotly Cloud [[#7802](https://github.com/plotly/plotly.js/pull/7802), [#7852](https://github.com/plotly/plotly.js/pull/7852), [#7854](https://github.com/plotly/plotly.js/pull/7854)]. NOTE: The Plotly Cloud endpoint for receiving charts is not yet functional, so this button won't complete the upload.
-  - Fix stale `scattergl` error bars after toggling traces with mixed error bar visibility [[#7773](https://github.com/plotly/plotly.js/issues/7773)], with thanks to @JulienIcon for the contribution!
-  - Fix geo `fitbounds` to choose a compact longitude range when point data straddles the antimeridian [[#7837](https://github.com/plotly/plotly.js/pull/7837)], with thanks to @SharadhNaidu for the contribution!
+### Removed
+- Remove the deprecated Figure Factory functions `create_2d_density`, `create_annotated_heatmap`, `create_bullet`, `create_candlestick`, `create_choropleth`, `create_distplot`, `create_facet_grid`, `create_gantt`, `create_hexbin_mapbox`, `create_ohlc`, `create_scatterplotmatrix`, and `create_violin` [[#5627](https://github.com/plotly/plotly.py/pull/5627)]
+- Remove support for Kaleido versions less than v1.0.0 for static image generation [[#5677](https://github.com/plotly/plotly.py/pull/5677)]
+- Remove support for Orca for static image generation [[#5677](https://github.com/plotly/plotly.py/pull/5677)]
+- Remove `engine` argument from functions `fig.write_image()`,`fig.to_image()`, `pio.write_image()`, `pio.write_images()`, `pio.to_image()`, `pio.full_figure_for_development()`, and from renderer constructors [[#5677](https://github.com/plotly/plotly.py/pull/5677)]
 
 ### Updated
 - Update plotly.js from version 3.6.0 to version 4.0.0-rc.0 [[#5673](https://github.com/plotly/plotly.py/pull/5673)]. This is a major-version release candidate with many changes. See the [plotly.js release notes](https://github.com/plotly/plotly.js/releases/tag/v4.0.0-rc.0) for the full list. The most significant changes include:
-  - Add `quiver` trace type to visualize vector fields using arrows [[#7710](https://github.com/plotly/plotly.js/pull/7710)], with thanks to @degzhaus for the contribution!
+  - Add `quiver` trace type to visualize vector fields using arrows [[#7710](https://github.com/plotly/plotly.js/pull/7710)]
   - Add "Share Chart" modebar button for generating a chart-sharing link via Plotly Cloud [[#7909](https://github.com/plotly/plotly.js/pull/7909)]
   - Remove `scattermapbox`, `choroplethmapbox`, `densitymapbox` trace types, the `mapbox` subplot, and the `mapboxAccessToken` config option [[#7860](https://github.com/plotly/plotly.js/pull/7860)]. Use the equivalent `*map` traces instead.
     - The corresponding `graph_objects` and Plotly Express functions have also been removed in plotly.py; use the `map` versions instead
@@ -49,9 +53,22 @@ This project adheres to [Semantic Versioning](http://semver.org/).
     - New supported formats: `'#ff0000aa'`, `'#f00a'`, `'rgb(255 0 0)'`, `'rgba(255 0 0 / 0.5)'`, `'hsl(0 100% 50% / 0.5)'`, `'hsla(0, 100%, 50%, 0.5)'`, `'hwb(0, 0%, 0%)'` 
   - Replace `country-regex` with `country-iso-search` to search for country names in choropleth, scattergeo traces [[#7856](https://github.com/plotly/plotly.js/pull/7856)]. Most country names are handled exactly the same; a small number of legacy entries have been removed.
   - Change `layout.geo.fitbounds` default from `false` to `'locations'` [[#7895](https://github.com/plotly/plotly.js/pull/7895)]. `geo` subplots will now auto-fit the initial view to the trace data by default.
-  - Dynamically compute `center` and `zoom` values for `scattermap` and `densitymap` traces. The initial map view will now auto-fit to the trace data by default. Add `layout.map.fitbounds` attribute (default `'locations'`) to enable or disable auto-fitting behavior [[#7884](https://github.com/plotly/plotly.js/pull/7884), [#7913](https://github.com/plotly/plotly.js/pull/7913)], with thanks to @palmerusaf and @DhruvGarg111 for the contributions!
+  - Dynamically compute `center` and `zoom` values for `scattermap` and `densitymap` traces. The initial map view will now auto-fit to the trace data by default. Add `layout.map.fitbounds` attribute (default `'locations'`) to enable or disable auto-fitting behavior [[#7884](https://github.com/plotly/plotly.js/pull/7884), [#7913](https://github.com/plotly/plotly.js/pull/7913)]
   - Fix GeoJSON bounding-box computation for `choropleth` and `scattergeo` traces whose geometry crosses the antimeridian [[#7891](https://github.com/plotly/plotly.js/pull/7891)]
 
+## [6.9.0] - 2026-07-09
+
+### Fixed
+- Raise a clear `ValueError` when an unsupported marginal plot type is passed to Plotly Express, instead of failing later with a cryptic `'NoneType' object has no attribute 'constructor'` message [[#5625](https://github.com/plotly/plotly.py/pull/5625)], with thanks to @eugen-goebel for the contribution!
+- Read and write figure JSON files as UTF-8 in `read_json`/`write_json` so figures containing non-ASCII text are handled correctly on platforms whose default encoding is not UTF-8 (e.g. cp1252 on Windows) [[#5633](https://github.com/plotly/plotly.py/pull/5633)]
+
+
+### Updated
+- Update plotly.js from version 3.6.0 to version 3.7.0. See the plotly.js [release notes](https://github.com/plotly/plotly.js/releases/tag/v3.7.0) for more information [[#5639](https://github.com/plotly/plotly.py/pull/5639)]. Notable changes include:
+  - Rename `sendDataToCloud` modebar button to `sendChartToCloud`, and update to upload chart to Plotly Cloud [[#7802](https://github.com/plotly/plotly.js/pull/7802), [#7852](https://github.com/plotly/plotly.js/pull/7852), [#7854](https://github.com/plotly/plotly.js/pull/7854)]
+  - Fix stale `scattergl` error bars after toggling traces with mixed error bar visibility [[#7773](https://github.com/plotly/plotly.js/issues/7773)]
+  - Fix geo `fitbounds` to choose a compact longitude range when point data straddles the antimeridian [[#7837](https://github.com/plotly/plotly.js/pull/7837)]
+
 ## [6.8.0] - 2026-06-03
 
 ### Added

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -309,7 +309,7 @@ python commands.py updateplotlyjsdev --devrepo reponame --devbranch branchname
 
 This fetches the `plotly.js` in the CircleCI artifact of the branch `branchname` of the repo `reponame`.
 If `--devrepo` or `--devbranch` are omitted,
-`updateplotlyjsdev` defaults to `plotly/plotly.js` and `master` respectively.
+`updateplotlyjsdev` defaults to `plotly/plotly.js` and `main` respectively.
 
 ### Local Repository
 

diff --git a/_plotly_utils/basevalidators.py b/_plotly_utils/basevalidators.py
@@ -1118,16 +1118,18 @@ def validate_coerce(self, v):
 class ColorValidator(BaseValidator):
     """
     "color": {
-        "description": "A string describing color. Supported formats:
+        "description": "A string describing color. All CSS 4 color formats are supported, including:
                         - hex or short hex (e.g. '#d3d3d3', '#d3d')
                         - hex or short hex with alpha (e.g. '#d3d3d380', '#d3d8')
                         - rgb (e.g. 'rgb(255, 0, 0)', 'rgb(255 0 0)')
                         - rgba (e.g. 'rgba(255, 0, 0, 0.5)', 'rgba(255 0 0 / 0.5)')
                         - hsl (e.g. 'hsl(0, 100%, 50%)', 'hsl(0deg 100% 50%)')
                         - hsla (e.g. 'hsla(0, 100%, 50%, 0.5)', 'hsla(0deg 100% 50% / 0.5)')
-                        - hwb (e.g. 'hwb(0, 0%, 100%)', 'hwb(0 0% 100%)')
-                        - named colors(full list:
-                          http://www.w3.org/TR/css3-color/#svg-color)",
+                        - hwb (e.g. 'hwb(0 0% 100%)')
+                        - lab/lch/oklab/oklch (e.g. 'oklch(0.7 0.15 180)')
+                        - color (e.g. 'color(display-p3 1 0 0)')
+                        - named colors (full list: https://www.w3.org/TR/css-color-4/#named-color)
+                        - See full CSS 4 color spec: https://www.w3.org/TR/css-color-4/",
         "requiredOpts": [],
         "otherOpts": [
             "dflt",
@@ -1142,7 +1144,7 @@ class ColorValidator(BaseValidator):
         r"#([A-Fa-f0-9]{3}|[A-Fa-f0-9]{4}|[A-Fa-f0-9]{6}|[A-Fa-f0-9]{8})"
     )
     re_rgb_etc = re.compile(
-        r"((rgb|hsl)a?|hwb)\([\d.]+(%|deg)?([ ,] ?[\d.]+%?){2}([ /,] ?[\d.]+%?)?\)"
+        r"((rgb|hsl)a?|hwb|(ok)?(lab|lch))\([\d.]+(%|deg)?([ ,] ?[\d.]+%?){2}([ /,] ?[\d.]+%?)?\)|color\([\w-]+([ ,] ?[\d.]+){3,4}\)"
     )
     re_ddk = re.compile(r"var\(\-\-.*\)")
 
@@ -1323,8 +1325,11 @@ def description(self):
       - rgba (e.g. 'rgba(255, 0, 0, 0.5)', 'rgba(255 0 0 / 0.5)')
       - hsl (e.g. 'hsl(0, 100%, 50%)', 'hsl(0deg 100% 50%)')
       - hsla (e.g. 'hsla(0, 100%, 50%, 0.5)', 'hsla(0deg 100% 50% / 0.5)')
-      - hwb (e.g. 'hwb(0, 0%, 100%)', 'hwb(0 0% 100%)')
-      - a named CSS color: see https://plotly.com/python/css-colors/ for a list""".format(
+      - hwb (e.g. 'hwb(0 0% 100%)')
+      - lab/lch/oklab/oklch (e.g. 'oklch(0.7 0.15 180)')
+      - color (e.g. 'color(display-p3 1 0 0)')
+      - named colors (full list: https://www.w3.org/TR/css-color-4/#named-color)
+      - Any other supported CSS 4 color format: https://www.w3.org/TR/css-color-4/""".format(
             plotly_name=self.plotly_name
         )