improve personal data export

app/controllers/Account.scala

@@ -426,7 +426,9 @@ final class Account(
 
   def data =
     Auth { implicit ctx => me =>
-      val userId = get("user").ifTrue(isGranted(_.Impersonate)) | me.id
+      val userId = get("user")
+        .map(lila.user.User.normalize)
+        .filter(id => me.id == id || isGranted(_.Impersonate)) | me.id
       env.user.repo byId userId flatMap {
         _ ?? { user =>
           env.api.personalDataExport(user) map { raw =>

app/views/account/bits.scala

@@ -16,7 +16,7 @@ object bits {
         h1("My personal data"),
         div(cls := "personal-data__header")(
           p("Here is all personal information Lichess has about ", userLink(u)),
-          a(cls := "button", href := s"${routes.Account.data()}?text=1")(trans.downloadRaw())
+          a(cls := "button", href := s"${routes.Account.data()}?user=${u.id}&text=1")(trans.downloadRaw())
         ),
         st.section(
           pre(cls := "raw-text")(raw)