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For a level 3 threshold crossing in the historic period the combined threshold icon for a location will look as follows:
Since 2017.01 a button is available to turn of the threshold icons, it can be recognized by its icon: 
. While this button is activated, the threshold icons are shown on the map (as normal). When the button is deactivated, the threshold icons will be deactivated, thus allowing the location type and data availability and validation icons to become visible.
Search in list boxes
It is possible to search elements in the list boxes. Select the appropriate list box and start typing the search criteria, see examples below. The cursor jumps to the next element starting with the letters you typed; in determining a match a closing asterisk "*" is implied. You may also use the asterisk "*" explicitly in the search criteria, for example if you do not want to start with the first character of the elements in the list box. When the search criteria turns red, the search criteria can not be found.
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