merging. All elements of each group will form one after the operation.
<ul>
<li>\b Remove button deletes the selected group from the list.</li>
<li>\b Add button adds to the list a group of elements selected in the
viewer with pressed "Shift" key.</li>
<li><b>Select all</b> checkbox selects all groups.</li>
merging. All elements of each group will form one after the operation.
<ul>
<li>\b Remove button deletes the selected group from the list.</li>
<li>\b Add button adds to the list a group of elements selected in the
viewer with pressed "Shift" key.</li>
<li><b>Select all</b> checkbox selects all groups.</li>