Prevent browser autocomplete for milestone date fields

app/views/shared/milestones/_form_dates.html.haml

@@ -2,10 +2,10 @@
   .form-group.row
     = f.label :start_date, "Start Date", class: "col-form-label col-sm-2"
     .col-sm-10
-      = f.text_field :start_date, class: "datepicker form-control", placeholder: "Select start date"
+      = f.text_field :start_date, class: "datepicker form-control", placeholder: "Select start date", autocomplete: 'off'
       %a.inline.float-right.prepend-top-5.js-clear-start-date{ href: "#" } Clear start date
   .form-group.row
     = f.label :due_date, "Due Date", class: "col-form-label col-sm-2"
     .col-sm-10
-      = f.text_field :due_date, class: "datepicker form-control", placeholder: "Select due date"
+      = f.text_field :due_date, class: "datepicker form-control", placeholder: "Select due date", autocomplete: 'off'
       %a.inline.float-right.prepend-top-5.js-clear-due-date{ href: "#" } Clear due date

changelogs/unreleased/48153-date-selection-dialog-broken-when-creating-a-new-milestone.yml

+---
+title: Prevent browser autocomplete for milestone date fields
+merge_request:
+author:
+type: fixed