in src/model/transaction/removeRangeFromContentState.js [224:236]
nextSibling: getNextValidSibling(block, blocks, originalBlockMap),
prevSibling: getPrevValidSibling(block, blocks, originalBlockMap),
}),
),
);
// if parent (startBlock) was deleted
if (
blockMap.get(startBlock.getKey()) == null &&
blockMap.get(endBlock.getKey()) != null &&
endBlock.getParentKey() === startBlock.getKey() &&
endBlock.getPrevSiblingKey() == null
) {