Single-Line Input: A question placeholder disappears when switching from Preview to Edit mode

[JaneSjs]

T17047 - Placeholder in text-components disappears after preview
https://surveyjs.answerdesk.io/internal/ticket/details/T17047

---

{
 "title": "my choices",
 "pages": [
  {
   "name": "page1",
   "elements": [
    {
     "type": "text",
     "name": "text1",
     "placeholder": "placeholder"
    },
    {
     "type": "dropdown",
     "name": "dropdown1",
     "placeholder": "placeholder dropdown"
    }
   ]
  }
 ],
 "showPrevButton": false,
 "showQuestionNumbers": "off",
 "questionErrorLocation": "bottom",
 "showPreviewBeforeComplete": "showAnsweredQuestions"
}

Edit Mode:

Preview:

Edit: a placeholder disappears.