diff --git a/filebrowser_quantum/CHANGELOG.md b/filebrowser_quantum/CHANGELOG.md
index b7c9aa0bc9..883d56a4e9 100644
--- a/filebrowser_quantum/CHANGELOG.md
+++ b/filebrowser_quantum/CHANGELOG.md
@@ -1,6 +1,6 @@
  
 ## 2.0.0.1 (2026-10-11)
-- Fix startup on 2.0.0 (fresh installs and upgrades): write the v2 config format (`http.port`/`listen`/`baseURL`, `server.database.path`), drop the deprecated `FILEBROWSER_DATABASE` variable, and migrate an existing 1.x `/config/database.db` to `/config/database.sqlite` on first start (#3109)
+- Fix startup on 2.0.0 (fresh installs and upgrades): write the v2 config format (`http.port`/`listen`/`baseURL`, `server.database.path`) and drop the deprecated `FILEBROWSER_DATABASE` variable (#3109) - Upgrade from 1.x: the old `/config/config.yaml` is saved as `config.yaml.v1.bak` and replaced by the 2.0 default (1.x keys are rejected by 2.0), and the 1.x `/config/database.db` is migrated to `/config/database.sqlite` on first start
 
 ## 2.0.0 (2026-10-10)
 - Update to latest version from gtsteffaniak/filebrowser (changelog : https://github.com/gtsteffaniak/filebrowser/releases)
diff --git a/filebrowser_quantum/rootfs/etc/cont-init.d/99-run.sh b/filebrowser_quantum/rootfs/etc/cont-init.d/99-run.sh
index c1c4f445e7..e75c75b92e 100755
--- a/filebrowser_quantum/rootfs/etc/cont-init.d/99-run.sh
+++ b/filebrowser_quantum/rootfs/etc/cont-init.d/99-run.sh
@@ -79,6 +79,13 @@ mkdir -p /var/log/nginx && touch /var/log/nginx/error.log
 
 mkdir -p /config /cache
 
+# A 1.x config (string server.database, written below before 2.0.0) holds keys
+# that v2 rejects: keep a copy and start again from the v2 default
+if [ -f "$FILEBROWSER_CONFIG" ] && [ "$(yq e '.server.database | tag' "$FILEBROWSER_CONFIG")" = "!!str" ]; then
+    bashio::log.warning "FileBrowser 1.x config saved to ${FILEBROWSER_CONFIG}.v1.bak, starting from the 2.0 default config"
+    mv "$FILEBROWSER_CONFIG" "${FILEBROWSER_CONFIG}.v1.bak"
+fi
+
 # Copy default config if not existing
 if [ ! -f "$FILEBROWSER_CONFIG" ]; then
     cp /home/filebrowser/data/config.yaml "$FILEBROWSER_CONFIG"
@@ -88,8 +95,6 @@ bashio::log.info "Updating FileBrowser config..."
 
 # --- Server (hardcoded values) ---
 bashio::log.info "... set server"
-# v2 moved port/listen/baseURL under http: and rejects the 1.x keys
-yq e -i "del(.server.port, .server.listen, .server.baseURL)" "$FILEBROWSER_CONFIG"
 yq e -i ".http.port = 8080"              "$FILEBROWSER_CONFIG"
 yq e -i ".http.listen = \"0.0.0.0\""    "$FILEBROWSER_CONFIG"
 yq e -i ".server.database = {\"path\": \"/config/database.sqlite\"}" "$FILEBROWSER_CONFIG"