v1.39.0

Added

• Add distributed npm packages for the main plotly.js bundle and all our partial
  bundles for easy installation and bundling [#2670]
• Add template machinery along with helpers methods Plotly.makeTemplate and
  Plotly.validateTemplate [#2764]
• Add 3D streamtube traces [#2658]
• Add support for on-graph text in scattergl traces [#2737, #2783]
• Add gridshape attribute to polar subplots with values 'circular' (the
  default) and 'linear' (to draw polygon grids) [#2739]
• Add 'range' and 'change' aggregate transform functions [#2764]
• Add visible attribute to rangeselector and updatemenu buttons, slider
  steps and mapbox layout layers as well as tickformatstops items [#2761]
• Add support for colorbar linked to marker.color values for splom,
  scatterpolar and scatterpolargl traces [#2681]
• Revamp icon settings in custom mode bar buttons, allowing users to specify
  their own dimensions and SVG transforms [#2762]
• Add plotlyServerURL config option [#2760]
• Added no-WebGL warnings for graphs with scattergl, scatterpolargl, splom
  and parcoords traces [#2697]

Changed

• plotly_afterplot is now emitted after all edit types [#2773]
• Trace uid is no longer mutated into user trace objects [#2681]
• No longer add marker.line in scattermapbox fullData [#2766]
• Use regl@1.3.6 [#2694]
• Use mapbox-gl@0.45.0 [#2709]

Fixed

• Fix Plotly.react's handling of changing auto-margins [#2681]
• Make plotting/updating WebGL-based traces fail gracefully when WebGL isn't
  supported [#2697]
• Fix mapbox layout layer updates [#2734]
• Fix mapbox event inconsistencies [#2766]
• Correctly emit plotly_relayout at end of scroll on mapbox subplots [#2709]
• Fix scatter3d scalar hovertext handling [#2698]
• Fix line decimation for segments crossing the viewport [#2705]
• Fix surface trace contours when first level has length zero [#2712]
• Fix contour(x|y|z).highlight partial settings [#2712]
• Fix old date timezone precision in Chrome 67+ [#2747]
• Fix Plotly.validate for attribute with trailing numbers (e.g. x0, y1) [#2761]
• Fix x-only zoom moves when xaxis.fixedrange: true[#2776]
• Fix colorbar edits for parcoords and histogram traces [#2681]
• Fix bandwidth for single-value violins [#2775]
• Sanitize margin after 'autosize' relayouts [#2758]
• Make Plots.resize work when layout attribute is gone from graph div [#2710]
• Fix colorscale attribute descriptions [#2658]