diff --git a/internal/agent/ssh.go b/internal/agent/ssh.go
index 06150cf..ccb6dfa 100644
--- a/internal/agent/ssh.go
+++ b/internal/agent/ssh.go
@@ -244,7 +244,7 @@ func (a *Agent) runSSH(parent context.Context, sid string, t proto.SSHTarget) {
 		}
 	}()
 	log.Printf("ssh %s: %s@%s up (host key %s)", sid, t.User, addr, fp)
-	status(proto.SSHOK, t.User+"@"+addr+" · "+fp)
+	status(proto.SSHOK, t.User+"@"+addr)
 	a.bridgeStream(parent, sid, sh, sh.Resize)
 	log.Printf("ssh %s: ended", sid)
 }
diff --git a/internal/agent/update.go b/internal/agent/update.go
index c1c3a91..d7bc1d6 100644
--- a/internal/agent/update.go
+++ b/internal/agent/update.go
@@ -3,31 +3,40 @@ package agent
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
+	"log"
 	"net/http"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"runtime"
+	"strings"
+	"syscall"
 	"time"
 
 	"github.com/x-grk/longpolling-remote-access/internal/proto"
 )
 
-// doUpdate downloads the latest agent binary for this platform, atomically
-// replaces the running executable, and schedules a service restart. It never
-// uninstalls - only updates.
+// doUpdate downloads the latest agent binary for this platform, replaces the
+// running executable and restarts the service. It runs as root when it can:
+// the agent's own user if that is root, otherwise sudo when it needs no
+// password. It never uninstalls - only updates.
 func (a *Agent) doUpdate() proto.TaskResult {
 	exe, err := os.Executable()
 	if err != nil {
 		return proto.TaskResult{Error: "не удалось определить путь бинарника: " + err.Error()}
 	}
 	exe, _ = filepath.EvalSymlinks(exe)
+	sudo := ""
+	if os.Geteuid() != 0 {
+		sudo = sudoPath()
+	}
 
 	url := fmt.Sprintf("%s/download/agent-%s-%s", a.cfg.Host, runtime.GOOS, runtime.GOARCH)
 	req, _ := http.NewRequestWithContext(context.Background(), http.MethodGet, url, nil)
-	resp, err := a.http.Do(req)
+	resp, err := a.stream.Do(req)
 	if err != nil {
 		return proto.TaskResult{Error: "скачивание: " + err.Error()}
 	}
@@ -36,41 +45,125 @@ func (a *Agent) doUpdate() proto.TaskResult {
 		return proto.TaskResult{Error: "скачивание: сервер вернул " + resp.Status}
 	}
 
-	tmp := exe + ".new"
-	f, err := os.OpenFile(tmp, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0o755)
-	if err != nil {
-		return proto.TaskResult{Error: "создание файла: " + err.Error()}
+	// The new binary lands next to the old one, or, when root's hand is
+	// needed to put it there, in a temporary folder first.
+	dir := filepath.Dir(exe)
+	if sudo != "" {
+		dir = ""
 	}
-	if _, err := io.Copy(f, resp.Body); err != nil {
-		f.Close()
-		os.Remove(tmp)
+	f, err := os.CreateTemp(dir, ".lpagent-new-*")
+	if err != nil {
+		return proto.TaskResult{Error: "создание файла: " + err.Error() + userNote()}
+	}
+	tmp := f.Name()
+	defer os.Remove(tmp)
+	n, err := io.Copy(f, io.LimitReader(resp.Body, 256<<20))
+	if cerr := f.Close(); err == nil {
+		err = cerr
+	}
+	if err != nil {
 		return proto.TaskResult{Error: "запись: " + err.Error()}
 	}
-	f.Close()
+	if err := checkBinary(tmp, n); err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
+	if err := os.Chmod(tmp, 0o755); err != nil {
+		return proto.TaskResult{Error: err.Error()}
+	}
 
-	// Atomic replace: renaming over a running executable is allowed on Linux;
-	// the live process keeps the old inode until it restarts.
-	if err := os.Rename(tmp, exe); err != nil {
-		os.Remove(tmp)
-		return proto.TaskResult{Error: "замена бинарника: " + err.Error()}
+	how := "от " + currentUser()
+	if sudo != "" {
+		// install copies it in place under a new inode, as a rename would.
+		if out, err := exec.Command(sudo, "-n", "install", "-m", "0755", tmp, exe).CombinedOutput(); err != nil {
+			return proto.TaskResult{Error: "замена бинарника через sudo: " + strings.TrimSpace(string(out)+" "+err.Error())}
+		}
+		how = "через sudo"
+	} else if err := os.Rename(tmp, exe); err != nil {
+		// Renaming over a running executable is allowed; the live process
+		// keeps the old inode until it restarts.
+		return proto.TaskResult{Error: "замена бинарника: " + err.Error() + userNote()}
 	}
 
 	// Restart shortly, after the result has been reported.
 	go func() {
 		time.Sleep(1500 * time.Millisecond)
-		restartSelf()
+		restartSelf(exe, sudo)
 	}()
 
-	data, _ := json.Marshal(map[string]string{"status": "обновлено, перезапуск"})
+	data, _ := json.Marshal(map[string]string{"status": "обновлено " + how + ", перезапуск"})
 	return proto.TaskResult{OK: true, Data: data}
 }
 
-// restartSelf restarts the agent so the new binary takes effect.
-func restartSelf() {
-	if path, err := exec.LookPath("systemctl"); err == nil {
-		_ = exec.Command(path, "restart", "lpagent").Start()
-		return
+// sudoPath is sudo when it lets this user run commands without a password.
+func sudoPath() string {
+	p, err := exec.LookPath("sudo")
+	if err != nil {
+		return ""
+	}
+	if exec.Command(p, "-n", "true").Run() != nil {
+		return ""
+	}
+	return p
+}
+
+func userNote() string {
+	if os.Geteuid() == 0 {
+		return ""
+	}
+	return " (агент запущен от " + currentUser() + ", без root и sudo без пароля - обновите установщиком)"
+}
+
+// checkBinary makes sure what came is a program for this system, not an
+// error page: a binary of a sensible size with the right header.
+func checkBinary(path string, size int64) error {
+	if size < 1<<20 {
+		return fmt.Errorf("скачанный файл слишком мал (%d байт) - не похоже на агента", size)
+	}
+	f, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	var magic [4]byte
+	if _, err := io.ReadFull(f, magic[:]); err != nil {
+		return err
+	}
+	ok := false
+	switch runtime.GOOS {
+	case "linux":
+		ok = string(magic[:]) == "\x7fELF"
+	case "darwin":
+		ok = magic == [4]byte{0xcf, 0xfa, 0xed, 0xfe} || magic == [4]byte{0xca, 0xfe, 0xba, 0xbe}
+	default:
+		ok = true
+	}
+	if !ok {
+		return errors.New("скачанный файл - не программа для " + runtime.GOOS)
+	}
+	return nil
+}
+
+// restartSelf starts the new binary. Under systemd the service is restarted
+// (queued, so it goes on after this process is stopped); otherwise the
+// process replaces itself with the new binary.
+func restartSelf(exe, sudo string) {
+	if os.Getenv("INVOCATION_ID") != "" {
+		if path, err := exec.LookPath("systemctl"); err == nil {
+			args := []string{"--no-block", "restart", "lpagent"}
+			cmd := exec.Command(path, args...)
+			if sudo != "" {
+				cmd = exec.Command(sudo, append([]string{"-n", path}, args...)...)
+			}
+			if cmd.Run() == nil {
+				return
+			}
+		}
+		// systemd brings a service that stopped back up (Restart=always).
+		os.Exit(0)
+	}
+	CloseTerminals()
+	if err := syscall.Exec(exe, os.Args, os.Environ()); err != nil {
+		log.Printf("update: restart: %v", err)
+		os.Exit(0)
 	}
-	// No systemd (e.g. launchd/manual run): exit so the supervisor restarts us.
-	os.Exit(0)
 }
diff --git a/internal/server/handlers_panel.go b/internal/server/handlers_panel.go
index d81f3e9..70bf5a6 100644
--- a/internal/server/handlers_panel.go
+++ b/internal/server/handlers_panel.go
@@ -211,6 +211,8 @@ func (s *Server) handleAgentEdit(w http.ResponseWriter, r *http.Request) {
 		"ServerVersion": Version,
 		"Outdated":      a.Version != "" && a.Version != Version,
 		"Updated":       r.URL.Query().Get("updated") == "1",
+		"UpdateMsg":     r.URL.Query().Get("umsg"),
+		"UpdateErr":     r.URL.Query().Get("uperr"),
 		"UserOK":        r.URL.Query().Get("uok"),
 		"UserErr":       r.URL.Query().Get("uerr"),
 		"Transport":     firstNonEmpty(a.Transport, proto.TransportAuto),
@@ -366,17 +368,28 @@ func (s *Server) handleAgentUpdate(w http.ResponseWriter, r *http.Request) {
 		http.NotFound(w, r)
 		return
 	}
+	back := func(q url.Values) { http.Redirect(w, r, "/agents/"+id+"/edit?"+q.Encode(), http.StatusSeeOther) }
 	if !s.online(a) {
-		http.Redirect(w, r, "/agents/"+id+"/edit?updated=0", http.StatusSeeOther)
+		back(url.Values{"uperr": {"машина не в сети"}})
 		return
 	}
-	taskID, ch := s.hub.CreateTask(id, proto.TaskSysUpdate, nil)
-	defer s.hub.DiscardTask(taskID)
-	select {
-	case <-ch:
-	case <-time.After(30 * time.Second):
+	if admin := s.currentAdmin(r); admin != nil {
+		s.db.Audit(admin.ID, id, "update:"+a.Version+" -> "+Version)
+	}
+	// The download can take a while on a slow link; under a proxy's timeout.
+	res, err := s.waitTask(r.Context(), id, proto.TaskSysUpdate, nil, 80*time.Second)
+	switch {
+	case err != nil:
+		back(url.Values{"uperr": {"агент не ответил: " + err.Error()}})
+	case !res.OK:
+		back(url.Values{"uperr": {res.Error}})
+	default:
+		var d struct {
+			Status string `json:"status"`
+		}
+		_ = json.Unmarshal(res.Data, &d)
+		back(url.Values{"updated": {"1"}, "umsg": {d.Status}})
 	}
-	http.Redirect(w, r, "/agents/"+id+"/edit?updated=1", http.StatusSeeOther)
 }
 
 func (s *Server) handleAgentRename(w http.ResponseWriter, r *http.Request) {
diff --git a/internal/server/web/static/account.js b/internal/server/web/static/account.js
index 056741b..7cc43e5 100644
--- a/internal/server/web/static/account.js
+++ b/internal/server/web/static/account.js
@@ -53,7 +53,7 @@
     '  <input type="password" name="current" inputmode="numeric" maxlength="4" pattern="[0-9]{4}" placeholder="текущий PIN" autocomplete="off">' +
     '  <input type="password" name="pin" inputmode="numeric" maxlength="4" pattern="[0-9]{4}" placeholder="новый PIN, 4 цифры" autocomplete="off">' +
     '  <input type="password" name="again" inputmode="numeric" maxlength="4" pattern="[0-9]{4}" placeholder="новый ещё раз" autocomplete="off">' +
-    '  <div class="row"><button type="button" class="btn danger small acct-pindel">Убрать PIN</button><button type="submit" class="acct-pinsave">Сохранить</button></div>' +
+    '  <div class="row"><button type="button" class="btn danger acct-pindel">Убрать PIN</button><button type="submit" class="acct-pinsave">Сохранить</button></div>' +
     '  </form>' +
     '  <label class="acct-pingrace"><span>На этом устройстве не спрашивать после ввода</span><select>' +
     '  <option value="0">каждый раз</option><option value="5">5 минут</option><option value="15">15 минут</option>' +
diff --git a/internal/server/web/static/terminal.js b/internal/server/web/static/terminal.js
index b2733d6..50f17e0 100644
--- a/internal/server/web/static/terminal.js
+++ b/internal/server/web/static/terminal.js
@@ -287,6 +287,7 @@
     t.el.querySelector('.dot').className = 'dot ' + (st.includes('err') ? 'err' : st.includes('wait') ? 'wait' : st.includes('ok') ? 'ok' : 'off');
     t.el.classList.toggle('on', t === active);
     t.view.classList.toggle('split', t.panes.length > 1);
+    syncFloat();
   }
   function activate(t) {
     if (!t) return;
@@ -310,8 +311,13 @@
     statusEl.title = activePane.text;
     statusEl.className = activePane.state === 'ok' ? 'st-ok' : activePane.state === 'err' ? 'st-err' : 'muted';
   }
+  // The corner "+" moves down out of the way of a split tab's title bars.
+  function syncFloat() {
+    document.body.classList.toggle('split1', tabs.length === 1 && tabs[0].panes.length > 1);
+  }
   // One tab: a plain terminal, the strip folded into the corner "+".
   function updateMode() {
+    syncFloat();
     const multi = tabs.length > 1;
     if (document.body.classList.contains('multi') === multi) return;
     document.body.classList.toggle('multi', multi);
diff --git a/internal/server/web/templates/edit.html b/internal/server/web/templates/edit.html
index 292099c..62910ae 100644
--- a/internal/server/web/templates/edit.html
+++ b/internal/server/web/templates/edit.html
@@ -94,7 +94,8 @@
 
   <div class="card">
     <h2>Версия клиента</h2>
-    {{if .Updated}}<div class="err" style="background:#1d3a24;border-color:#2b6b3a;color:#b3ffcb">Команда обновления отправлена. Клиент скачает свежий бинарник и перезапустится.</div>{{end}}
+    {{if .Updated}}<div class="err" style="background:#1d3a24;border-color:#2b6b3a;color:#b3ffcb">Клиент {{if .UpdateMsg}}{{.UpdateMsg}}{{else}}обновлён и перезапускается{{end}}. Через несколько секунд он вернётся с новой версией.</div>{{end}}
+    {{if .UpdateErr}}<div class="err">Обновление не вышло: {{.UpdateErr}}</div>{{end}}
     <p class="muted">
       Клиент: <code>{{if .Agent.Version}}{{.Agent.Version}}{{else}}неизвестно{{end}}</code>
       · Сервер: <code>{{.ServerVersion}}</code>
diff --git a/internal/server/web/templates/files.html b/internal/server/web/templates/files.html
index 1394ccc..3d79792 100644
--- a/internal/server/web/templates/files.html
+++ b/internal/server/web/templates/files.html
@@ -16,6 +16,7 @@
   }
   /* A button with an icon before its text. */
   .fm-bar .btn.ico { gap:6px; }
+  .fm-bar .spacer { flex:1; }
   input.fm-path { font-family:ui-monospace,Menlo,monospace; font-size:13px; color:var(--muted);
              background:#0c0f13; border:1px solid var(--border); border-radius:8px; padding:8px 12px;
              flex:1; min-width:200px; height:34px; box-sizing:border-box; }
@@ -58,7 +59,9 @@
   table.fm td, table.fm th { padding:7px 8px; }
   .fm .nm { cursor:pointer; }
   .fm .nm:hover { color:var(--accent); }
-  .ic { display:inline-block; width:18px; text-align:center; margin-right:6px; }
+  .ic { display:inline-flex; vertical-align:-3px; width:18px; justify-content:center; margin-right:6px; color:var(--muted); }
+  .ic.dir { color:#7aa7d9; }
+  .ic.dir svg { fill:rgba(122,167,217,.16); }
   .sz { color:var(--muted); font-variant-numeric:tabular-nums; }
   .act { display:flex; gap:6px; justify-content:flex-end; }
   /* Sortable headers: a click sorts by the column, a second one turns it round. */
@@ -76,6 +79,8 @@
     table.fm td, table.fm th { padding:7px 4px; }
     .ic { margin-right:4px; }
     .fm-bar .fm-pathbox { flex:1 1 100%; order:-1; }
+    /* The selection's buttons go together on a line of their own. */
+    .fm-bar .spacer { flex:1 1 100%; height:0; }
   }
   dialog { background:var(--panel); color:var(--text); border:1px solid var(--border);
            border-radius:12px; padding:0; max-width:900px; width:92vw; }
@@ -304,7 +309,7 @@
     <button class="btn small ico" id="mkdir"><svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.2" stroke-linecap="round" stroke-linejoin="round"><path d="M22 19a2 2 0 0 1-2 2H4a2 2 0 0 1-2-2V5a2 2 0 0 1 2-2h5l2 3h9a2 2 0 0 1 2 2z"/><path d="M12 11v6M9 14h6"/></svg>Папка</button>
     <button class="btn small ico" id="newfile"><svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.2" stroke-linecap="round" stroke-linejoin="round"><path d="M14 2H6a2 2 0 0 0-2 2v16a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2V8z"/><path d="M14 2v6h6M12 12v6M9 15h6"/></svg>Файл</button>
     <label class="btn small ico" style="cursor:pointer"><svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.2" stroke-linecap="round" stroke-linejoin="round"><path d="M12 3v12M6 10l6 6 6-6M5 21h14"/></svg>Загрузить<input type="file" id="upl" multiple hidden></label>
-    <span class="spacer" style="flex:1"></span>
+    <span class="spacer"></span>
     <span id="selinfo" class="muted" style="font-size:13px"></span>
     <button class="btn ghost small" id="zipsel" disabled>В zip</button>
     <button class="btn danger small" id="delsel" disabled>Удалить выбранное</button>
@@ -482,6 +487,30 @@
   const ICON_MV   = SVG + '<polyline points="5 9 2 12 5 15"/><polyline points="9 5 12 2 15 5"/><polyline points="15 19 12 22 9 19"/><polyline points="19 9 22 12 19 15"/><line x1="2" y1="12" x2="22" y2="12"/><line x1="12" y1="2" x2="12" y2="22"/></svg>';
   const ICON_UNZIP = SVG + '<rect x="2" y="3" width="20" height="5" rx="1"/><path d="M4 8v11a2 2 0 0 0 2 2h2"/><path d="M20 8v11a2 2 0 0 1-2 2h-2"/><path d="m9 15 3-3 3 3"/><path d="M12 12v9"/></svg>';
   const ICON_DEL  = SVG + '<path d="M3 6h18"/><path d="M8 6V4a2 2 0 0 1 2-2h4a2 2 0 0 1 2 2v2"/><path d="M19 6l-1 14a2 2 0 0 1-2 2H8a2 2 0 0 1-2-2L5 6"/><line x1="10" y1="11" x2="10" y2="17"/><line x1="14" y1="11" x2="14" y2="17"/></svg>';
+  // File icons: one colour, the line style of the buttons; a few kinds by
+  // the name's ending.
+  const FI = '<svg class="fi" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round">';
+  const FICONS = {
+    dir:  FI + '<path d="M3 7a2 2 0 0 1 2-2h4l2 2.5h8a2 2 0 0 1 2 2V17a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2z"/></svg>',
+    file: FI + '<path d="M14 3H7a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h10a2 2 0 0 0 2-2V8z"/><path d="M14 3v5h5"/></svg>',
+    text: FI + '<path d="M14 3H7a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h10a2 2 0 0 0 2-2V8z"/><path d="M14 3v5h5M9 13h6M9 17h4"/></svg>',
+    code: FI + '<path d="M14 3H7a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h10a2 2 0 0 0 2-2V8z"/><path d="M14 3v5h5M10 12l-2 2.5 2 2.5M14 12l2 2.5-2 2.5"/></svg>',
+    img:  FI + '<rect x="3" y="4" width="18" height="16" rx="2"/><circle cx="9" cy="10" r="1.6"/><path d="m21 16-5-5-8 9"/></svg>',
+    arc:  FI + '<path d="M14 3H7a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h10a2 2 0 0 0 2-2V8z"/><path d="M14 3v5h5M11 4v2M11 8v2M11 12v2"/><rect x="9.5" y="15" width="3" height="3" rx=".6"/></svg>',
+    media:FI + '<rect x="3" y="5" width="18" height="14" rx="2"/><path d="m10 9 5 3-5 3z"/></svg>',
+    link: FI + '<path d="M10 14a4 4 0 0 0 5.7 0l3-3a4 4 0 0 0-5.7-5.7l-1 1"/><path d="M14 10a4 4 0 0 0-5.7 0l-3 3a4 4 0 0 0 5.7 5.7l1-1"/></svg>'
+  };
+  function fileIcon(e) {
+    let k = 'file';
+    if (e.is_dir) k = 'dir';
+    else if (/^L/.test(e.mode || '')) k = 'link';
+    else if (/\.(png|jpe?g|gif|webp|bmp|ico|svg|avif|heic)$/i.test(e.name)) k = 'img';
+    else if (/\.(zip|tar|gz|tgz|bz2|xz|zst|7z|rar|deb|rpm)$/i.test(e.name)) k = 'arc';
+    else if (/\.(mp4|m4v|webm|mov|mkv|avi|mp3|wav|ogg|flac|m4a|aac|opus)$/i.test(e.name)) k = 'media';
+    else if (/\.(js|ts|go|py|rb|rs|c|h|cpp|java|kt|php|sh|bash|zsh|json|ya?ml|toml|html?|css|sql|lua|pl|swift|vue|jsx|tsx|ini|conf|xml)$/i.test(e.name)) k = 'code';
+    else if (/\.(txt|md|log|csv|rst|cfg|env)$|^(readme|license|makefile|dockerfile)/i.test(e.name)) k = 'text';
+    return '<span class="ic' + (k === 'dir' ? ' dir' : '') + '">' + FICONS[k] + '</span>';
+  }
   let cwd = '/';
   let entries = [];
   const selected = new Set();
@@ -564,7 +593,7 @@
       const dlHref = '/api/panel/agents/' + encodeURIComponent(agentID) + '/fs/download?path=' + encodeURIComponent(join(cwd, e.name));
       tr.innerHTML =
         '<td><input type="checkbox" class="ck" data-n="'+encodeURIComponent(e.name)+'"></td>' +
-        '<td class="nm"><span class="ic">'+(e.is_dir?'📁':'📄')+'</span>'+esc(e.name)+'</td>' +
+        '<td class="nm">'+fileIcon(e)+esc(e.name)+'</td>' +
         '<td class="sz c-sz">'+(e.is_dir?'':fmtSize(e.size))+'</td>' +
         '<td class="sz mt">'+fmtTime(e.mtime)+'</td>' +
         '<td><div class="act">' +
diff --git a/internal/server/web/templates/terminal.html b/internal/server/web/templates/terminal.html
index 659f85f..b84bd31 100644
--- a/internal/server/web/templates/terminal.html
+++ b/internal/server/web/templates/terminal.html
@@ -82,7 +82,9 @@
   body.multi .area { margin-top:0; border-top-left-radius:0; }
   .float-add { position:absolute; top:8px; right:10px; z-index:6; width:28px; height:28px; padding:0; display:inline-flex;
                align-items:center; justify-content:center; font-size:17px; line-height:1; color:var(--text);
-               background:transparent; border:1px solid var(--border); opacity:.28; transition:opacity .25s ease, background .25s ease; }
+               background:transparent; border:1px solid var(--border); opacity:.28; transition:opacity .25s ease, background .25s ease, top .25s ease; }
+  /* One tab split in panes: below the panes' title bars, clear of their close buttons. */
+  body.split1 .float-add { top:42px; }
   .float-add:hover, .float-add:focus-visible { opacity:1; background:var(--panel); }
   body.multi .float-add { opacity:0; pointer-events:none; }
   .tabview { position:absolute; inset:8px; opacity:0; visibility:hidden; transform:translateY(4px) scale(.995);