I can't replicate this so far. I have an entity like this and I can edit it in studio without issues.
{
"name": "t",
"engine": "handlebars",
"recipe": "chrome-pdf",
"shortid": "YDk7AYwFfX",
"creationDate": {
"$$date": 1673020613229
},
"modificationDate": {
"$$date": 1673285032858
},
"_id": "khiOoblGOqkQn9bg",
"$entitySet": "templates",
"chrome": {
"printBackground": true
}
}
Could you try it in a private browser window? Maybe there is something wrong cached in the browser.