v0.331.0: OnlyOffice opens and saves from FileBrowser and Nextcloud; FileBrowser back at once after a restart (R-1018)

FileBrowser config carries server.internalUrl http://filebrowser:80 (OnlyOffice fetched the public files address and got 403);
Nextcloud's DocumentServerInternalUrl gets its trailing slash (every save was lost: http://onlyoffice:80cache/...);
RestartStack("filebrowser") runs the R-1126 gate at once (files.<domain> was 502 for up to 5 min after the link switched).
Each red-proofed. MinAgent 0.158.1.

CHANGELOG.md

@@ -1,3 +1,29 @@
+## v0.331.0 — OnlyOffice opens and SAVES from FileBrowser and Nextcloud; FileBrowser is back at once after a restart (R-1018) (2026-10-18)
+
+**MinAgent: 0.158.1** — the floor's, carried (not above the vouched agent 0.159.2). Nothing here calls a new agent route.
+No golden (`09` §3 decision 250). Task: the evening brief of 2026-10-18 (felhom.eu `REPORT-evening-2026-10-18.md`).
+Found by the first live walk of the OnlyOffice links since the move to Proxmox (scratch 9202, headless Chrome through the
+box's public names; felhom.eu `audits/onlyoffice-2026-10-18/`).
+
+- **FileBrowser → OnlyOffice could not open a document.** FileBrowser built the download and save URLs it hands
+  OnlyOffice from the request's host, `https://files.<domain>` — a trip out through the tunnel and back (on demo-hp it
+  reached another box: 403). FileBrowser's config now carries `server.internalUrl: "http://filebrowser:80"` (used by
+  integrations only, gtstef/filebrowser:1.5.6-stable `onlyOffice.go`); OnlyOffice reaches it by name on traefik-public,
+  where the R-1126 gate puts it. Every box's FileBrowser config changes once, so FileBrowser is re-created once.
+  `TestFileBrowserConfig_R1018_InternalURLIsTheContainer`.
+- **Nextcloud → OnlyOffice lost every edit.** `DocumentServerInternalUrl` was `http://onlyoffice:80` with no slash, and
+  Nextcloud's connector appends paths: it fetched `http://onlyoffice:80cache/files/…` and logged „Track: … status 2
+  error", while the editor said „All changes saved". Now `http://onlyoffice:80/` (as `StorageUrl` already was). The occ
+  list is a function (`nextcloudApplyCommands`), so the test reads the values the apply really sends.
+  `TestNextcloudApply_R1018_InternalAddressesTakeAPath`. A box with the link already on gets the value at OnlyOffice's
+  or Nextcloud's next start (the link re-applies then).
+- **files.<domain> answered 502 for up to 5 minutes after the link switched on or off** (its Apply and Revoke restart
+  FileBrowser, and a re-created FileBrowser starts off traefik-public — R-1126 — until the next base-stack round;
+  measured 4 min 8 s and 3 min 38 s). `RestartStack("filebrowser")` now runs the gate at once, in the background, like
+  the mounts sync. `TestRestartStack_R1018_FileBrowserPublishedAgainAtOnce`.
+- Red-proofs: each fix removed → its test fails with the wrong value (felhom.eu `audits/onlyoffice-2026-10-18/redproof-fix{1,2,3}.txt`).
+- No page changed; every fixture byte-identical.
+
 ## Unreleased (2026-10-18) — CI workflow: the failure mail links the public run page, by run id (R-1135); no code change
 
 `.gitea/workflows/gates.yml`, the alarm step: the mail's run link is now `https://gitea.dooplex.hu/<repo>/actions/runs/<run id>`.

CONTEXT.md

@@ -1,6 +1,8 @@
 # CONTEXT.md — Project Memory
 
 
+> **2026-10-18 (evening) — v0.331.0: OnlyOffice opens and saves from FileBrowser (`server.internalUrl`) and Nextcloud
+> (`DocumentServerInternalUrl` with its slash); a FileBrowser restart runs the R-1126 gate at once (R-1018).** MinAgent 0.158.1.
 > **2026-10-18 (day) — v0.330.0: „anyway" asks the agent's disk list first and starts again the apps it stopped when the
 > agent refuses (R-1144).** MinAgent 0.158.1.
 > **2026-10-18 (night) — v0.329.0: each app reaches only its own `appdata/<folder>` (R-1142, compiled-in folder map:

REPORT.md

@@ -1,10 +1,21 @@
-# REPORT — controller v0.330.0 (2026-10-18, day)
+# REPORT — controller v0.331.0 (2026-10-18 evening): the OnlyOffice links, live-walked and fixed (R-1018)
 
-**In plain words.** When a household presses „retire anyway" and the host says no, the drive's apps start again, and
+Task: the evening brief of 2026-10-18, Part 2 (felhom.eu `REPORT-evening-2026-10-18.md`). Evidence: felhom.eu
-the household is told so. Where the host's own disk list already says no, nothing is stopped at all.
+`documentation/audits/onlyoffice-2026-10-18/`.
 
-| Row | Change | Pinned by | Red-proof |
+**The walk** (scratch 9202 on 0.330.0, OnlyOffice 9.4.0 + Nextcloud 34.0.4 installed through the dashboard API, headless
-|---|---|---|---|
+Chrome through the box's public names mapped to 9202):
-| R-1144 | precheck from the agent's disk list; restart exactly the apps that were running after a refusal | `TestR1144_*` (3) | no restart → starts = []; no precheck → 3 stops before the refusal |
 
-Gates: green gate rc=0; `controller_gates.py --fast` OK. Release path and box walk: felhom.eu `REPORT-day-2026-10-18.md`.
+| Path | Before the fix | After |
+|---|---|---|
+| FileBrowser → open a .docx | editor frame loads, the document never does: OnlyOffice's fetch of `https://files.<domain>/…` → 403 (the public name leads to another box) | opens, edits, saves: the file on the drive reads „R1018 BEFORE EDITED-FB-1849" |
+| Nextcloud → open a .docx | opens and edits; „All changes saved" — but the save is lost: Nextcloud fetches `http://onlyoffice:80cache/…` | the file in Nextcloud reads „… EDITED-NC-1847" |
+| switch the link on / off | files.<domain> 502 for 4 min 8 s / 3 min 38 s | the gate runs at the restart |
+| OnlyOffice stopped | FileBrowser: no editor; Nextcloud: `/apps/onlyoffice/<id>` 404 — the revoke-on-stop rule holds | — |
+
+**Fixes** (each red-proofed — the fix removed, the test failed with the wrong value, restored):
+1. FileBrowser config: `server.internalUrl: "http://filebrowser:80"` — `TestFileBrowserConfig_R1018_InternalURLIsTheContainer`.
+2. Nextcloud: `DocumentServerInternalUrl = http://onlyoffice:80/` — `TestNextcloudApply_R1018_InternalAddressesTakeAPath`.
+3. `RestartStack("filebrowser")` runs the R-1126 gate — `TestRestartStack_R1018_FileBrowserPublishedAgainAtOnce`.
+
+Gates: `go build/vet/test ./...` green; `controller_gates.py --fast` green. Fixtures: none changed.

controller/README.md

@@ -3893,7 +3893,7 @@ CRUD methods in settings.go: `GetIntegrationState`, `SetIntegrationState`, `Remo
 #### Built-in Handlers
 
 **OnlyOffice → FileBrowser** (`onlyoffice_filebrowser.go`):
-- Apply: Reads `JWT_SECRET` + `SUBDOMAIN` from OnlyOffice app.yaml (decrypted), strips any existing `integrations:` block from FileBrowser `config.yaml` via `removeIntegrationsSection()`, appends new block with `url` (public HTTPS), `internalUrl` (`http://onlyoffice:80`), `secret`, `viewOnly: false`. Atomic write (`.tmp` + rename). Restarts FileBrowser
+- Apply: Reads `JWT_SECRET` + `SUBDOMAIN` from OnlyOffice app.yaml (decrypted), strips any existing `integrations:` block from FileBrowser `config.yaml` via `removeIntegrationsSection()`, appends new block with `url` (public HTTPS), `internalUrl` (`http://onlyoffice:80`), `secret`, `viewOnly: false`. Atomic write (`.tmp` + rename). Restarts FileBrowser — and `RestartStack("filebrowser")` runs the R-1126 gate at once, so files.<domain> is back within seconds (v0.331.0, R-1018). OnlyOffice fetches and saves the document at FileBrowser's `server.internalUrl` (`http://filebrowser:80`, rendered in every FileBrowser config since v0.331.0) — never through the public address
 - Revoke: Strips `integrations:` block from config.yaml, restarts FileBrowser
 
 **OnlyOffice → Nextcloud** (`onlyoffice_nextcloud.go`):
@@ -3901,7 +3901,7 @@ CRUD methods in settings.go: `GetIntegrationState`, `SetIntegrationState`, `Remo
   1. `app:install onlyoffice` (tolerates "already installed")
   2. `app:enable onlyoffice`
   3. `config:app:set onlyoffice DocumentServerUrl --value=https://{subdomain}.{domain}`
-  4. `config:app:set onlyoffice DocumentServerInternalUrl --value=http://onlyoffice:80`
+  4. `config:app:set onlyoffice DocumentServerInternalUrl --value=http://onlyoffice:80/` (the trailing slash is load-bearing: the connector appends paths — without it every save failed, v0.331.0, R-1018)
   5. `config:app:set onlyoffice jwt_secret --value={JWT_SECRET}`
   6. `config:app:set onlyoffice StorageUrl --value=http://nextcloud` (internal callback URL)
 - Revoke: Runs `occ app:disable onlyoffice` (tolerates container not running / app not enabled)

controller/internal/infra/infra.go

@@ -459,6 +459,11 @@ func RenderFileBrowserConfigKept(paths []settings.StoragePath, importSource bool
 server:
   port: 80
   baseURL: "/"
+  # R-1018: the address OnlyOffice's server uses to fetch and save a document (FileBrowser's onlyOffice.go builds both
+  # URLs from it at gtstef/filebrowser:1.5.6-stable; it is used by integrations only). Without it FileBrowser hands
+  # OnlyOffice https://files.<domain> — a trip out through the tunnel and back, which failed (403) on demo-hp.
+  # Pinned by TestFileBrowserConfig_R1018_InternalURLIsTheContainer.
+  internalUrl: "http://filebrowser:80"
   # The box updates FileBrowser (the pinned image); a household cannot, so its „An update is available!" is noise.
   # backend/common/settings/structs.go:51 at gtstef/filebrowser:1.5.6-stable (v0.321.0).
   disableUpdateCheck: true

controller/internal/infra/infra_test.go

@@ -1,6 +1,8 @@
 package infra
 
 import (
+	"net/url"
+	"strconv"
 	"strings"
 	"testing"
 
@@ -248,6 +250,33 @@ func TestFileBrowserRender(t *testing.T) {
 	}
 }
 
+// R-1018: OnlyOffice's server fetches and saves a FileBrowser document at server.internalUrl. The consequence pinned:
+// that URL names the FileBrowser container on port 80 — the name OnlyOffice resolves on traefik-public — and the
+// container really is called that in the compose. RED-PROOF: drop the config line (FileBrowser then hands OnlyOffice
+// the public https://files.<domain>, 403 on demo-hp 2026-10-18) or rename the container → this fails.
+func TestFileBrowserConfig_R1018_InternalURLIsTheContainer(t *testing.T) {
+	var cfg struct {
+		Server struct {
+			InternalURL string `yaml:"internalUrl"`
+			Port        int    `yaml:"port"`
+		} `yaml:"server"`
+	}
+	if err := yaml.Unmarshal([]byte(RenderFileBrowserConfig([]settings.StoragePath{{Path: "/mnt/hdd_1"}}, true)), &cfg); err != nil {
+		t.Fatalf("config does not parse: %v", err)
+	}
+	u, err := url.Parse(cfg.Server.InternalURL)
+	if err != nil || u.Scheme != "http" || u.Hostname() == "" {
+		t.Fatalf("server.internalUrl = %q — OnlyOffice would be handed the public files address", cfg.Server.InternalURL)
+	}
+	if u.Port() != strconv.Itoa(cfg.Server.Port) {
+		t.Errorf("server.internalUrl port %q, FileBrowser listens on %d", u.Port(), cfg.Server.Port)
+	}
+	compose := RenderFileBrowserCompose("demo-felhom.eu", nil)
+	if !strings.Contains(compose, "container_name: "+u.Hostname()+"\n") {
+		t.Errorf("server.internalUrl names %q, which is not the FileBrowser container:\n%s", u.Hostname(), compose)
+	}
+}
+
 // R-1126 (D11 = A): FileBrowser starts OFF traefik-public — the box joins it there only after this run's default login
 // is checked — and on its own network, which the controller joins for that check. v0.327.1: NO Traefik labels — the
 // route is the file-provider route by NAME (a label route kept the address Traefik chose at container start, on the

controller/internal/integrations/onlyoffice_nextcloud.go

@@ -29,41 +29,7 @@ func (h *OnlyOfficeNextcloudHandler) Apply(ac *ApplyContext) error {
 	}
 
 	publicURL := fmt.Sprintf("https://%s.%s", subdomain, ac.Domain)
-	internalURL := "http://onlyoffice:80"
+	commands := nextcloudApplyCommands(publicURL, jwtSecret)
-
-	// Install and configure OnlyOffice app in Nextcloud
-	commands := []struct {
-		args     []string
-		tolerate string // substring in output to tolerate as success
-	}{
-		{
-			args:     []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "app:install", "onlyoffice"},
-			tolerate: "already installed",
-		},
-		{
-			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "app:enable", "onlyoffice"},
-		},
-		{
-			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:app:set", "onlyoffice", "DocumentServerUrl", "--value=" + publicURL},
-		},
-		{
-			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:app:set", "onlyoffice", "DocumentServerInternalUrl", "--value=" + internalURL},
-		},
-		{
-			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:app:set", "onlyoffice", "jwt_secret", "--value=" + jwtSecret},
-		},
-		{
-			// StorageUrl: tells OO Document Server where to reach Nextcloud internally for file callbacks.
-			// Trailing slash is critical — NC's OO connector does string replacement of the server URL
-			// (which ends with /) with StorageUrl. Without trailing slash, "/apps/..." merges into hostname.
-			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:app:set", "onlyoffice", "StorageUrl", "--value=http://nextcloud/"},
-		},
-		{
-			// Add internal hostname to trusted_domains so OO Document Server callbacks
-			// (arriving with Host: nextcloud) are not rejected by Nextcloud.
-			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:system:set", "trusted_domains", "10", "--value=nextcloud"},
-		},
-	}
 
 	for _, cmd := range commands {
 		ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
@@ -107,3 +73,52 @@ func (h *OnlyOfficeNextcloudHandler) Revoke(ac *ApplyContext) error {
 	ac.Logger.Printf("[INFO] [integrations] OnlyOffice integration revoked from Nextcloud")
 	return nil
 }
+
+// occCommand is one occ call of the apply; tolerate is a substring of its output that counts as success.
+type occCommand struct {
+	args     []string
+	tolerate string
+}
+
+// The two addresses OnlyOffice and Nextcloud use to reach each other inside the box. BOTH end with "/": Nextcloud's
+// OnlyOffice connector appends paths to them („converter", „cache/files/…", „apps/onlyoffice/track"). R-1018,
+// measured on demo-hp 2026-10-18: DocumentServerInternalUrl without the slash made Nextcloud fetch
+// http://onlyoffice:80cache/files/… — every save failed („Track: … status 2 error") while the editor said
+// „All changes saved". Pinned by TestNextcloudApply_R1018_InternalAddressesTakeAPath.
+const (
+	ncDocServerInternalURL = "http://onlyoffice:80/"
+	ncStorageURL           = "http://nextcloud/"
+)
+
+// nextcloudApplyCommands installs and configures the OnlyOffice app in Nextcloud.
+func nextcloudApplyCommands(publicURL, jwtSecret string) []occCommand {
+	return []occCommand{
+		{
+			args:     []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "app:install", "onlyoffice"},
+			tolerate: "already installed",
+		},
+		{
+			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "app:enable", "onlyoffice"},
+		},
+		{
+			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:app:set", "onlyoffice", "DocumentServerUrl", "--value=" + publicURL},
+		},
+		{
+			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:app:set", "onlyoffice", "DocumentServerInternalUrl", "--value=" + ncDocServerInternalURL},
+		},
+		{
+			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:app:set", "onlyoffice", "jwt_secret", "--value=" + jwtSecret},
+		},
+		{
+			// StorageUrl: tells OO Document Server where to reach Nextcloud internally for file callbacks.
+			// Trailing slash is critical — NC's OO connector does string replacement of the server URL
+			// (which ends with /) with StorageUrl. Without trailing slash, "/apps/..." merges into hostname.
+			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:app:set", "onlyoffice", "StorageUrl", "--value=" + ncStorageURL},
+		},
+		{
+			// Add internal hostname to trusted_domains so OO Document Server callbacks
+			// (arriving with Host: nextcloud) are not rejected by Nextcloud.
+			args: []string{"docker", "exec", "-u", "www-data", "nextcloud", "php", "occ", "config:system:set", "trusted_domains", "10", "--value=nextcloud"},
+		},
+	}
+}

controller/internal/integrations/onlyoffice_nextcloud_test.go

@@ -0,0 +1,44 @@
+package integrations
+
+import (
+	"net/url"
+	"strings"
+	"testing"
+)
+
+// R-1018: Nextcloud's OnlyOffice connector builds its server-to-server requests by APPENDING a path to the two inside
+// addresses the apply sets. The consequence pinned: the address the apply really sends, plus such a path, is a request
+// to the right container. Measured on demo-hp 2026-10-18: without the slash Nextcloud asked
+// http://onlyoffice:80cache/files/… and every save was lost. RED-PROOF: drop the slash from ncDocServerInternalURL →
+// the cache URL no longer parses (port "80cache") and this fails.
+func TestNextcloudApply_R1018_InternalAddressesTakeAPath(t *testing.T) {
+	values := map[string]string{}
+	for _, c := range nextcloudApplyCommands("https://office.example.hu", "secret") {
+		if len(c.args) >= 11 && c.args[7] == "config:app:set" {
+			values[c.args[9]] = strings.TrimPrefix(c.args[10], "--value=")
+		}
+	}
+	for _, tc := range []struct {
+		key, path, host string
+	}{
+		{"DocumentServerInternalUrl", "cache/files/data/2153553391_5872/output.docx/output.docx", "onlyoffice:80"},
+		{"DocumentServerInternalUrl", "converter?shardkey=thumb_1", "onlyoffice:80"},
+		{"StorageUrl", "apps/onlyoffice/track?doc=x", "nextcloud"},
+	} {
+		base, ok := values[tc.key]
+		if !ok {
+			t.Fatalf("the apply does not set %s (set: %v)", tc.key, values)
+		}
+		u, err := url.Parse(base + tc.path)
+		if err != nil {
+			t.Errorf("%s %q + %q is not a URL: %v", tc.key, base, tc.path, err)
+			continue
+		}
+		if u.Host != tc.host || !strings.HasPrefix(u.Path, "/"+strings.SplitN(tc.path, "?", 2)[0][:4]) {
+			t.Errorf("%s %q + %q reaches host %q path %q, want host %q", tc.key, base, tc.path, u.Host, u.Path, tc.host)
+		}
+	}
+	if values["DocumentServerUrl"] != "https://office.example.hu" {
+		t.Errorf("DocumentServerUrl = %q, want the public office address", values["DocumentServerUrl"])
+	}
+}

controller/internal/stacks/filebrowser_restart_gate_test.go

@@ -0,0 +1,132 @@
+package stacks
+
+import (
+	"context"
+	"fmt"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"gitea.dooplex.hu/admin/felhom-controller/internal/config"
+)
+
+// R-1018: the OnlyOffice link restarts FileBrowser (Apply and Revoke), and a re-created FileBrowser starts off
+// traefik-public (R-1126). The consequence pinned: after RestartStack("filebrowser") the NEW run is checked and joined to
+// traefik-public by itself, within seconds — not at the next base-stack round (files.<domain> answered 502 for 4 min 8 s
+// on demo-hp, 2026-10-18). Another app's restart publishes nothing. RED-PROOF: remove the gate call from RestartStack →
+// "not published again" (nothing connects until a round runs, and no round runs here).
+func TestRestartStack_R1018_FileBrowserPublishedAgainAtOnce(t *testing.T) {
+	if runtime.GOOS != "linux" {
+		t.Skip("the stub compose binary is a shell script")
+	}
+	fb := &fakeFB{password: "admin"}
+	srv := httptest.NewServer(fb.handler())
+	defer srv.Close()
+	m, _, _ := fbManager(t, srv.URL)
+
+	root := t.TempDir()
+	cfg := &config.Config{}
+	cfg.Paths.StacksDir = root
+	m.cfg = cfg
+	m.stacks = map[string]*Stack{}
+	for _, name := range []string{"filebrowser", "bookstack"} {
+		dir := filepath.Join(root, name)
+		if err := os.MkdirAll(dir, 0o755); err != nil {
+			t.Fatal(err)
+		}
+		if err := os.WriteFile(filepath.Join(dir, "docker-compose.yml"), []byte("services:\n  web:\n    image: nginx:1.27\n"), 0o644); err != nil {
+			t.Fatal(err)
+		}
+		m.stacks[name] = &Stack{Name: name, ComposePath: filepath.Join(dir, "docker-compose.yml"), Deployed: true}
+	}
+
+	// compose: a stub that records the recreate; docker inspect: the start time moves after it (RestartStack's own check).
+	bin := t.TempDir()
+	marker := filepath.Join(t.TempDir(), "recreated")
+	script := fmt.Sprintf("#!/bin/sh\nfor a in \"$@\"; do [ \"$a\" = \"--force-recreate\" ] && touch %q; done\nexit 0\n", marker)
+	if err := os.WriteFile(filepath.Join(bin, "docker-compose"), []byte(script), 0o755); err != nil {
+		t.Fatal(err)
+	}
+	t.Setenv("PATH", bin+string(os.PathListSeparator)+os.Getenv("PATH"))
+	m.composeCmd = "docker-compose"
+	m.execFn = func(string, ...string) (string, error) { return "", nil }
+	recreated := func() bool { _, err := os.Stat(marker); return err == nil }
+	m.installedExecFn = func(_ context.Context, _ string, _ []string, name string, args ...string) (string, error) {
+		if name == "docker" && len(args) > 0 && args[0] == "compose" {
+			name, args = "docker-compose", args[1:]
+		}
+		started := "2026-10-18T18:00:00Z"
+		if recreated() {
+			started = "2026-10-18T18:32:14Z"
+		}
+		switch {
+		case name == "docker-compose" && len(args) > 0 && args[0] == "ps":
+			return `{"ID":"aaa111bbb222","Name":"web-1","Service":"web"}`, nil
+		case name == "docker" && len(args) > 0 && args[0] == "inspect" && strings.Contains(strings.Join(args, " "), "State.StartedAt"):
+			return "aaa111bbb222ccc333" + inspectSep + "started" + inspectSep + started + "\n", nil
+		case name == "docker" && len(args) > 0 && args[0] == "inspect":
+			return "aaa111bbb222" + inspectSep + "nginx:1.27" + inspectSep + "sha256:i\n", nil
+		case name == "docker" && len(args) > 1 && args[0] == "image":
+			return "sha256:i" + inspectSep + "nginx@sha256:d\n", nil
+		}
+		return "", nil
+	}
+
+	// The gate's view of FileBrowser: run 1 was checked and public; a recreate makes run 2, off traefik-public.
+	var mu sync.Mutex
+	nets := map[string]bool{"filebrowser@traefik-public": true, "felhom-controller@felhom-filebrowser": true}
+	connected := make(chan string, 8)
+	m.fbStarted = func() string {
+		if recreated() {
+			return "run-2"
+		}
+		return "run-1"
+	}
+	m.fbProbedRun = "run-1"
+	m.fbNetOnFn = func(c, n string) bool { mu.Lock(); defer mu.Unlock(); return nets[c+"@"+n] }
+	m.fbNetConnectFn = func(c, n string) error {
+		mu.Lock()
+		nets[c+"@"+n] = true
+		mu.Unlock()
+		connected <- c + "@" + n
+		return nil
+	}
+
+	// Another app's restart publishes nothing.
+	if err := m.RestartStack("bookstack"); err != nil {
+		t.Fatalf("bookstack restart: %v", err)
+	}
+	select {
+	case c := <-connected:
+		t.Fatalf("a bookstack restart touched FileBrowser's networks: %s", c)
+	case <-time.After(300 * time.Millisecond):
+	}
+	os.Remove(marker)
+
+	// FileBrowser's restart: the recreate drops it from traefik-public; the gate must put run 2 back by itself.
+	mu.Lock()
+	delete(nets, "filebrowser@traefik-public")
+	mu.Unlock()
+	if err := m.RestartStack("filebrowser"); err != nil {
+		t.Fatalf("filebrowser restart: %v", err)
+	}
+	deadline := time.After(10 * time.Second)
+	for {
+		select {
+		case c := <-connected:
+			if c == "filebrowser@traefik-public" {
+				if m.fbProbedRun != "run-2" {
+					t.Fatalf("published, but the checked run is %q, not the new run-2", m.fbProbedRun)
+				}
+				return
+			}
+		case <-deadline:
+			t.Fatal("FileBrowser was not published again after its restart — files.<domain> stays 502 until a base-stack round")
+		}
+	}
+}

controller/internal/stacks/manager.go

@@ -1501,6 +1501,15 @@ func (m *Manager) RestartStack(name string) error {
 	}
 	m.mu.Unlock()
 
+	// R-1018: a re-created FileBrowser starts off traefik-public (R-1126), so files.<domain> answered 502 until the next
+	// base-stack round — up to 5 minutes, measured 4 min 8 s on demo-hp 2026-10-18 after the OnlyOffice link switched
+	// on (its Apply and Revoke restart FileBrowser). Check and publish this run now, in the background like the mounts
+	// sync does (handlers.go): the check may wait ~20 s for FileBrowser to answer, and it takes infraMu, which no caller
+	// of RestartStack holds. Pinned by TestRestartStack_R1018_FileBrowserPublishedAgainAtOnce.
+	if name == fileBrowserContainer {
+		go m.EnsureFileBrowserGate()
+	}
+
 	return m.RefreshStatus()
 }