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Group elements, on the other hand, require some explanation. You cannot create new groups. If you want to add new groups, then you need to call the AddGroups method. Instead, any Group element in this tag must include a Key attribute that references an existing group. Everything inside the group tag is then handled normally, just as it would have been handled in the Init method.
The SplitButton element must reference an existing split button (using the Key attribute) only if it appears within this AddControls tag. If it appears within any other tag, then it is treated as a new control.
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