New features in 2.20 since 2.18
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+ • A new ‘output-attributes’ grob property is now used for svg output
+ instead of the ‘id’ grob property. It allows multiple attributes
+ to be defined as an association list. For example, ‘#'((id . 123)
+ (class . foo) (data-whatever . “bar”))’ will produce the following
+ group tag in an SVG file: ‘<g id=“123” class=“foo”
+ data-whatever=“bar”> ... </g>’.
+
• Slurs and phrasing slurs may now be started from individual notes
in a chord. Several simultanous slurs per ‘Voice’ need to be
distinguished by ‘spanner-id’ setting.