diff --git a/infra/youtube-backup/.env.example b/infra/youtube-backup/.env.example
index 72e4984..01ddf17 100644
--- a/infra/youtube-backup/.env.example
+++ b/infra/youtube-backup/.env.example
@@ -14,8 +14,8 @@ YOUTUBE_BACKUP_COOKIES_FROM_BROWSER=
 
 YOUTUBE_BACKUP_FORMAT=bv*+ba/best
 YOUTUBE_BACKUP_MERGE_FORMAT=mp4
-YOUTUBE_BACKUP_SUB_LANGS=all,-live_chat
 YOUTUBE_BACKUP_JS_RUNTIMES=node
+YOUTUBE_BACKUP_WRITE_THUMBNAIL=false
 YOUTUBE_BACKUP_SLEEP_REQUESTS=1
 YOUTUBE_BACKUP_RATE_LIMIT=
 YOUTUBE_BACKUP_EXTRA_ARGS=
diff --git a/infra/youtube-backup/README.md b/infra/youtube-backup/README.md
index 7ae160a..141fc55 100644
--- a/infra/youtube-backup/README.md
+++ b/infra/youtube-backup/README.md
@@ -62,6 +62,11 @@ Downloaded videos and sidecar metadata are written under:
 /data/youtube-backup/videos
 ```
 
+The default backup writes the video, `.info.json`, description, and embeds one
+thumbnail into the media file. It does not write separate subtitle files. Set
+`YOUTUBE_BACKUP_WRITE_THUMBNAIL=true` if you also want one sidecar `.jpg`
+thumbnail.
+
 Each run also writes a timestamped log under:
 
 ```text
diff --git a/infra/youtube-backup/backup-youtube.sh b/infra/youtube-backup/backup-youtube.sh
index 95d59ac..67e099e 100755
--- a/infra/youtube-backup/backup-youtube.sh
+++ b/infra/youtube-backup/backup-youtube.sh
@@ -20,9 +20,9 @@ COOKIES_FILE="${YOUTUBE_BACKUP_COOKIES_FILE:-}"
 COOKIES_FROM_BROWSER="${YOUTUBE_BACKUP_COOKIES_FROM_BROWSER:-}"
 FORMAT="${YOUTUBE_BACKUP_FORMAT:-bv*+ba/best}"
 OUTPUT_TEMPLATE="${YOUTUBE_BACKUP_OUTPUT_TEMPLATE:-%(playlist_title)s/%(upload_date>%Y-%m-%d,release_date>%Y-%m-%d,epoch>%Y-%m-%d)s - %(title)s [%(id)s].%(ext)s}"
-SUB_LANGS="${YOUTUBE_BACKUP_SUB_LANGS:-all,-live_chat}"
 MERGE_FORMAT="${YOUTUBE_BACKUP_MERGE_FORMAT:-mp4}"
 JS_RUNTIMES="${YOUTUBE_BACKUP_JS_RUNTIMES:-node}"
+WRITE_THUMBNAIL="${YOUTUBE_BACKUP_WRITE_THUMBNAIL:-false}"
 RATE_LIMIT="${YOUTUBE_BACKUP_RATE_LIMIT:-}"
 SLEEP_REQUESTS="${YOUTUBE_BACKUP_SLEEP_REQUESTS:-1}"
 EXTRA_ARGS="${YOUTUBE_BACKUP_EXTRA_ARGS:-}"
@@ -68,16 +68,16 @@ args=(
     --restrict-filenames
     --write-info-json
     --write-description
-    --write-thumbnail
-    --write-subs
-    --write-auto-subs
-    --sub-langs "${SUB_LANGS}"
     --embed-metadata
     --embed-thumbnail
     --js-runtimes "${JS_RUNTIMES}"
     --sleep-requests "${SLEEP_REQUESTS}"
 )
 
+if [[ "${WRITE_THUMBNAIL}" == "true" ]]; then
+    args+=(--write-thumbnail --convert-thumbnails jpg)
+fi
+
 if [[ -n "${COOKIES_FILE}" ]]; then
     args+=(--cookies "${COOKIES_FILE}")
 fi