Count and display how many times values changed in a column - google-apps-script

Question

At the start sorry for my poor english, i will try my best to explain everything.
Is there a way to count how many times value in column D has been changed and show it in column E?
In this example in column D person can select two values from list - "☐" and "☑". In column E i would want to see how many times person changed their selection. Lets say for for E3 i want to see how many time D3 was changed, for E4 to show how many times D4 was change and so on.
Thank you for all help!
Example spreadsheet
The only thing i found was somehitng like that:
function onEdit(e) {
if(e.range.getA1Notation() == "D2") {
var sCounter = e.source.getRange("E2");
var counter = sCounter.getValue();
if(counter === 0) {
counter = 1;
} else {
counter ++;
}
sCounter.setValue(counter);
}
}
The problem is that it only counts one cell and i need it to work for the whole column.

Answer 1

This should do it:
function onEdit(e) {
var ss =SpreadsheetApp.getActiveSpreadsheet()
var s=ss.getActiveSheet()
var editColumn=e.range.getColumn()
var editRow = e.range.getRow()
if(editColumn == 4 && editRow >=2) {
var sCounter = s.getRange(editRow,editColumn+1,1,1);
var counter = sCounter.getValue();
if(counter === 0) {
counter = 1;
} else {
counter ++;
}
sCounter.setValue(counter);
}}
Here is my test spreadsheet you can copy and try:
https://docs.google.com/spreadsheets/d/1I5_NVMKPvqN9J2sSlcLRnQbzoVF4iRKOuXJ5mshb-RY/edit?usp=sharing