Here some recommendations to make it better and essentials

[onigetoc]

1 - Adding row on right with
insert a new row before
insert a new row after
BTW, you cannot add a row after the last row
2 - Adding row want you hit Enter when you are on the last row. if you use Enter often it should do a row everytime.
3 - Allowing a search bar to filter element with the entire row.
4 - Double click on top row A, B,C ect to toggle row order.
5 - Clicking on the first cell, the top left select all.
6 - Using multiple cells selection for mobile and tablet like Microsoft Excel.
7 - Allowing loading json file. ( I got some partial success trying to implement it, see bellow )
8 - Adding a Calendar for date.

I got some partial success trying to load .json files

`function transformJson(json) {
let data = [];
let rows = [];

if (!json || json.length === 0) {
return data;
}

let headers = [];

if (json[0]) {
headers = Object.keys(json[0]);
} else {
console.error('Le tableau JSON est vide ou ne contient pas d'éléments.');
return data;
}

let headerRow = {
cells: {}
};

headers.forEach((header, index) => {
headerRow.cells[index] = {
text: header
};
});

rows.push(headerRow);

json.forEach((row) => {
let rowData = { cells: {} };

headers.forEach((header, index) => {
  rowData.cells[index] = {
    text: row[header]
  };
});

rows.push(rowData);

});

data.push({
name: "Sheet1",
rows: rows,
merges: []
});

return data;
}
`