code.gs

```
var runSelect = true
function onSelectionChange(e) {
  var sheet = SpreadsheetApp.getActiveSheet()
  var range = e.range;
  var column = range.getColumn();
  var lastRow = sheet.getLastRow();
  var ui = SpreadsheetApp.getUi();
  if (runSelect == true) {
    sheet.getRange(5, column, lastRow-4).activate();
    sheet.getRange(1, column).copyTo(sheet.getActiveRange());
    ui.alert("Finnish")

```

I have try to change my selection, but alert never show and not do copy
['https://Stackoverflow.com/questions/61929649', 'https://Stackoverflow.com', 'https://Stackoverflow.com/users/13578315/']
I just faced the same issue on a new spreadsheet with a new project having only a very simple `onSelectionChange`:

```
function onSelectionChange(e) {
  console.log(JSON.stringify(e));
}

```

After reopening the spreadsheet (refreshing the web browser tab), the `onSelectionChange` worked fine.
Same issue happened to me. I run the code manually from the editor and it asked for authorization. I authorized it and viola! Now the onSelectionChange trigger works! I hope it may be helpful for someone passing by...