setActiveCell on all sheets within a spreadsheet. Google Apps Script

Question

I have a Google spreadsheet with multiple sheets. I would like the cursor to be set to a particular cell onOpen for all tabs. Each cell of the first row represents

Answer 1

Looks like you need to make a call to SpreadsheetApp.flush() when you loop over the sheets collection:

function onOpen() {
  SpreadsheetApp.getActive().getSheets().forEach(function (s) {
    s.setActiveSelection("B4");
    SpreadsheetApp.flush(); // Force this update to happen
  });
}

My guess is Apps Script's execution engine optimizes the writes to a single call, and in that single call only one active selection can be made. Calling flush forces 1 call per sheet to be updated.