relativeOffsetsToGlobalOffsets(start, startOffset, end, endOffset) {
        return domManager.relativeOffsetsToGlobalOffsets(start, startOffset, end, endOffset);
      }
Calculates relative offsets to global offsets for a given range in the document.

@param {Node} start - The starting node of the range.
@param {number} startOffset - The offset within the starting node.
@param {Node} end - The ending node of the range.
@param {number} endOffset - The offset within the ending node.
@return {number[]|undefined} - An array containing the calculated global offsets in codepoints in the form of [startGlobalOffset, endGlobalOffset].