fix: the username and picture (#3638)

Co-authored-by: dni ⚡ <office@dnilabs.com>

lnbits/static/js/components/lnbits-header.js

@@ -38,12 +38,6 @@ window.app.component('lnbits-header', {
     customLogoUrl() {
       return this.USE_CUSTOM_LOGO || null
     },
-    userPictureUrl() {
-      return this.g.user.extra.picture
-    },
-    hasUserPicture() {
-      return this.g.user && this.g.user.extra && this.g.user.extra.picture != ''
-    },
     showAdmin() {
       return this.g.user && (this.g.user.super_user || this.g.user.admin)
     },
@@ -53,6 +47,7 @@ window.app.component('lnbits-header', {
     displayName() {
       return (
         this.g.user?.extra?.display_name ||
+        this.g.user.username ||
         this.g.user?.extra?.first_name ||
         'Anon'
       )