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Since 2017.02 for shape-layers containing points, class breaks are allowed to use icons instead of colors. If both class breaks containing icons and a pointIconId is specified, the pointIconId is used as a default when no class break applies. It is also used in the image displayed before the layer name in the layer selection panel. Note that this image will only be loaded if the layer has been loaded, i.e., was ever visible during the current session. A config example is shown below.
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