Google Sheets: split cells vertically and copy surrounding row entries - google-apps-script

Question

I need to do the following to optimize this sheet:
split each multi-line cell in column B so each email address will appear on a new row inserted under the original row.
Copy the data from cells in column A on the original row
I tried split+transpose formulas and a script I found here, but that is returning an error.
Here is the script:
function split_rows2(anArray) {
var res = anArray.reduce(function(ar, e) {
var splitted = e.slice(3, 12).map(function(f) {return f.toString().split(",").map(function(g) {return g.trim()})});
var temp = [];
for (var j = 0; j < splitted[0].length; j++) {
temp.push(e.slice(0, 3).concat(splitted.map(function(f) {return f[j] ? (isNaN(f[j]) ? f[j] : Number(f[j])) : ""})).concat(e.slice(12, 20)));
}
Array.prototype.push.apply(ar, temp);
return ar;
}, []);
return res;
}

Answer 1

=ArrayFormula(QUERY(SPLIT(FLATTEN({A2:A&"♦"&SPLIT(B2:B,",")}),"♦"),"select * where Col2 is not null",0))
Before:
Col1
Col2
A
1,2,3
B
4,5
After:
Col1
Col2
A
1
A
2
A
3
B
4
B
5

Answer 2

A multiline cell implies that they are delimited by line feeds '\n' not commas
function myfunk() {
const ss = SpreadsheetApp.getActive();
const sh = ss.getSheetByName('Sheet0');
let vs = sh.getRange(2, 1, sh.getLastRow() - 1, sh.getLastColumn()).getValues();
sh.getRange(2, 1, sh.getLastRow() - 1, sh.getLastColumn()).clearContent();
vs.forEach((r, i) => {
let t = r[1].toString().split('\n');
if (t.length > 1) {
t.forEach((e, j) => {
if(j == 0) {
r[1] = e;
} else {
let arr = Array.from(r, x => '');
arr[1] = e;
vs.splice(i + j, 0 , arr)
}
});
}
});
sh.getRange(2, 1, vs.length, vs[0].length).setValues(vs);
}
Sheet 0 after:
COL1
COL2
COL3
COL4
0
4
19
17
5
8
10
7
0
a
21
19
b
c
9
14
17
0