Portainer Agent: use alpine-sts upstream image (#3011)

* fix(portainer-agent): use alpine-sts upstream image

* fix(portainer-agent): align STS updater versioning

portainer_agent/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 2.44.0 (2026-08-23)
+
+- Fix: Use `portainer/agent:alpine-sts` to match the STS release channel configured in `updater.json`
+- Fix: Align add-on versioning with Portainer STS releases
+
 ## 2025.12.7 (2026-08-23)
 
 - Fix: Docker reported the addon as `unhealthy` in Portainer. The healthcheck script could never run because its shebang required the s6-overlay environment, which this addon's entrypoint does not set up (https://github.com/alexbelgium/hassio-addons/issues/3002)

portainer_agent/Dockerfile

@@ -18,7 +18,7 @@
 ARG BUILD_FROM
 
 # Get agent
-FROM portainer/agent:alpine as original_agent
+FROM portainer/agent:alpine-sts as original_agent
 ENV PORTAINER_AGENT_ARGS=""
 
 # Build using base

portainer_agent/config.yaml

@@ -41,4 +41,4 @@ schema:
 slug: portainer_agent
 udev: true
 url: https://github.com/alexbelgium/hassio-addons
-version: "2025.12.7"
+version: "2.44.0"

portainer_agent/updater.json

@@ -1,6 +1,6 @@
 {
-  "github_tagfilter": "alpine",
-  "last_update": "24-12-2025",
+  "github_tagfilter": "sts",
+  "last_update": "23-08-2026",
   "repository": "alexbelgium/hassio-addons",
   "slug": "portainer_agent",
   "source": "dockerhub",