Breaking changes:

• Stop parsing the deprecated 8-digit ‘YYYYMMDD’ date format (#984) (#985) (#1023)
• GWT “support” is no longer pertinent as we cannot recompile the binary JAR; the latter is still available from the website for now

New features:

• Add option to colour the range selector’s veil (#856)
• Added strokeStyle option to crosshair plugin (#955)
• Support DocumentFragment as a result from a legendFormatter function (#958) (#959)
• Add data index to legendFormatter data (#965)
• Implement #RRGGBB[AA] hex colour parsing
• Make animateBackgroundFade into an option
• Add new “resizable” option using ResizeObserver on maindiv + CSS
• Add offset config for legend div in follow mode (#946)

Bugfixes:

• Fix duplicate annotation when having duplicate points (#826)
• Make sure that canvasx and canvasy properties are initialised from the start (#896)
• Fix issue #781 when the y range is zero (#909)
• Synchroniser now calls highlightCallback (#935)
• Fix drawAxes to allow one of two Y axes to be drawn (#936)
• LEGEND: Don’t show Y if value is undefined (#853) (#947)
• Fixed 'Cannot read property 'length' of undefined' issue (#962) (#963)
• Two fixes in the calculations of pinch-zoom (#990)
• Fix for double paint of grid of x-axis (#1007)
• Fix number of days in a year (#1012)
• Fix labelsKMB and labelsKMG2 (#571) (#994) (#1022)
• Fix label position in onmouseover legend mode was never updated
• Fix several cases of mispositioning/missizing by enabling elements before using offsetWidth etc.
• Make it possible to use logscale (and sigma, wilsonInterval) per-axis (#986)

Other user-visible changes:

• Documentation is now shipped (mostly self-contained) in the release
• Tests that use Google JSAPI are now marked ⚠ and no other external content is loaded anywhere
• Calculate legend positioning relative to closest data point (#1013)
• Add missing documentation about annotations xval option (#992)
• source mapping URLs are now correct (#1027)
• Ship ES5 versions of extras (#952), use them in examples
• Fix documentation/website HTML/CSS/JS bugs (#979) (#1008)
• On the website, external links are now clearly labelled
• The documentation and website now have browsable subdirectories by manually generated directory index files
• Link to UNPKG as CDN as well (to keep neutral; use of CDNs in websites violates the EU-GDPR)
• Most issues with right-to-left languages should now be fixed (#1019)
• Document that Dygraph will misbehave if the main div has padding

Internal refactors/fixes:

• Use link href, not link src (#904)
• Add missing semicolon in externs (#964)
• Large build system improvements relying in large parts on Debian and GHA
• Full licence review as part of uploading to Debian (#1024) (#1025) (#1029); drop embedded code copies
• Fix some JSDoc warnings
• Update to contemporary versions of Python 3, jQuery, Babel, etc.
• Add copies of design documents that were previously only available on Google Docs or part of GitHub issues to offline documentation
• Nuke useless semicola after function declaration bodies
• Fix closure type annotation in hairlines.js
• Remove already commented-out obsolete, or redundant, code

• Double click event can be captured and cancelled by plugins
• setAnnotations's second parameter is now an optional boolean
• Add `pixelRatio` option, which may allow improved performance on smaller screens by controlling the canvas' pixel ratio
• X-axis label and tick logic can now operate at millisecond-level granularity

• Repair a bug in "Custom interaction modals" demo

• Fix various spelling mistakes
• Fix a couple of type signatures in dygraph-externs.js

• JS files were renamed to dygraph.js and dygraph.min.js.
• There's now a dygraph.css file that you must include.
• Dropped support for OldIE and other non-standard browsers. dygraphs works in IE11. I'm not sure about IE9 and IE10.
• Double-click to unzoom zooms all the way out (and ignores valueRange).
• Dropped old-style per-axis/per-series options.

• Add a legendFormatter option
• `this` is the Dygraph object in all callbacks
• pass through (row, col) to valueFormatter
• Option to not sync range in extras/synchronizer.js
• Additional options for styling the range selector
• getRowForX method
• setVisibility can set the visibility of multiple series at once.
• crosshair plugin extra
• rebase/straw broom plugin
• highlightSeriesBackgroundColor option
• yAxisExtremes() method.
• Passing strings in native format now throws. (Previously it kinda sorta worked.)

• Selections are always cleared with animations
• synchronizer calls previously-set callbacks
• synchronizer only syncs when graphs are ready
• Reset on synchronized graphs failed
• fix to improve synchronizer performance
• binary search bug fix in synchronizer
• Fix range selection when chart is located inside fullscreen element
• fillAlpha can be set per-series when fillGraph is set.
• xRangePad was ignored on unzoom
• Allow selected points where canvas-y coordinate is 0
• Using valueRange with Logscale and yRangePad has unexpected results
• With "drawGapEdgePoints", unwanted point often drawn at beginning of chart

• “legend: follow” positioning changes

• Code moved into a “src/“ directory
• Tests use Mocha instead of jstd
• dygraphs is split into ES6 modules and uses some ES6 features (e.g. arrows and destructuring).
• dygraphs is built using babel & browserify
• Code coverage is tracked continuously
• Bundle size is now tracked continuously

• Set this to the dygraph in all callbacks.
• Minor bug fixes.

• dygraphs is now "retina" compatible.
• Dramatically improved performance for filled charts (i.e. fillGraph)
• More sensible date ticks: "Jan 08"→"Jan 2008", "29Jan"→"29 Jan"
• Using a non-existent option now throws (w/ dygraph-combined-dev.js)
• x-axis log scales
• The labelsUTC option forces UTC formatting for all labels.
• The new DataHandler system allows for more flexibility in data loading.
• "this" is set to the dygraph in all callbacks.
• dygraphs has shrunk, because we moved some stuff into "extras" (133kb→122kb)