diff --git a/README.md b/README.md
index d689234..4350e41 100644
--- a/README.md
+++ b/README.md
@@ -48,7 +48,7 @@ Start the Target panel with no arguments:
 proxyctl
 ```
 
-Press `m` for Proxy Profile management, then `n` to create a Profile, enter a name and proxy URL, and press Ctrl+S to save. The editor supports cursor movement, Home, End, Delete, Backspace, insertion, paste, and horizontal scrolling; Tab or the arrow keys move between fields, and Escape cancels without saving. Validation stays beside each field. The management page supports reviewing obscured connection details, editing, and safe deletion; Active Profile switching remains a separate dashboard picker workflow rather than a management action. Single mode applies one URL to HTTP, HTTPS, and ALL/SOCKS. Ctrl+T selects advanced mode for separate values without discarding values entered in either mode. A bare `host:port` is accepted and normalized to `http://`. The Single proxy URL field visibly offers Protocol Probe with Ctrl+D; it runs only on that explicit keypress, and its credential-safe progress and HTTP/SOCKS5 result stay with the affected URL field rather than global status. When one endpoint supports both protocols, the probe switches the form to advanced mode and fills HTTP/HTTPS with `http://` and ALL/SOCKS with `socks5://`. Bypass accepts comma- or newline-delimited hostnames, domain suffixes, IPv4, IPv6, and CIDR entries; the editor previews normalized, deduplicated values and identifies invalid items before save.
+Press `m` for Proxy Profile management, then `n` to create a Profile, enter a name and proxy URL, and press Ctrl+S to save. The editor supports cursor movement, Home, End, Delete, Backspace, insertion, paste, and horizontal scrolling; Tab or the arrow keys move between fields, and Escape cancels without saving. Validation stays beside each field. The management page supports reviewing obscured connection details, editing, and safe deletion; Active Profile switching remains a separate dashboard picker workflow rather than a management action. Single mode applies one URL to HTTP, HTTPS, and ALL/SOCKS. Ctrl+T selects advanced mode for separate values without discarding values entered in either mode. A bare `host:port` is accepted and normalized to `http://`. The Single proxy URL field visibly offers Protocol Probe with Ctrl+D; it runs only on that explicit keypress, and its credential-safe progress and HTTP/SOCKS5 result stay with the initiating URL context rather than global status. When one endpoint supports both protocols, the probe switches the form to advanced mode, retains a read-only Single URL probe source row, and fills HTTP/HTTPS with `http://` and ALL/SOCKS with `socks5://`. Bypass accepts comma- or newline-delimited hostnames, domain suffixes, IPv4, IPv6, and CIDR entries; the editor previews normalized, deduplicated values and identifies invalid items before save.
 
 The dashboard shows the Active Profile. Press `p` to open the searchable Active Profile picker, type to filter, use arrows to select, and press Enter to activate; Escape cancels without changing the Active Profile. Use arrows or `j`/`k` to select an Available Target and Space to run its contextual action: Enable, Disable, Apply Profile, or Resolve. Drift Resolution explicitly offers Reapply Active Profile and Restore Original; restoration refuses safely if proxyctl no longer has sufficient ownership evidence. Press `r` to refresh detection, `u` to show unavailable Targets, and `?` on any page or dialog for contextual Help. Help scrolls with arrows, `j`/`k`, Page Up/Page Down, Home, and End; `q` or Escape closes it without changing the page, focus, selection, or viewport beneath it. Applying or reapplying requires an Active Profile, while Restore Original remains available without one.
 
@@ -116,7 +116,7 @@ Inspect failures and rerun until reset reports no failed managed Target. Then re
 
 ## Privacy and safety boundaries
 
-proxyctl has no telemetry, automatic update checks, or automatic proxy-connectivity tests. It does not contact the network on its own; the only network traffic it generates is the user-initiated Protocol Probe (Ctrl+D in the Profile form), a handshake check that never forwards traffic through the proxy and never contacts anything beyond the endpoint itself. Local diagnostic logs are credential-redacted and bounded in size. Proxy credentials remain present where a selected Target requires them, so normal local file security still matters.
+proxyctl has no telemetry, automatic update checks, or automatic proxy-connectivity tests. It does not contact the network on its own; the only network traffic it generates is the user-initiated Protocol Probe (Ctrl+D in the Profile form), a handshake check that never forwards traffic through the proxy and never contacts anything beyond the endpoint itself. Local diagnostic logs are credential-redacted and bounded in size. Profile form frames mask the entire URL userinfo while retaining the underlying value for saving. Proxy credentials remain present where a selected Target requires them, so normal local file security still matters.
 
 proxyctl does **not** manage or supervise proxy processes such as Clash, sing-box, or Xray. It does not manage subscriptions, nodes, latency, routing rules, transparent proxying, TUN/iptables/nftables, arbitrary services or commands, plugins, or a complete headless Profile/Target CLI.
 
diff --git a/internal/profile/profile.go b/internal/profile/profile.go
index 973e18f..5e7b1d7 100644
--- a/internal/profile/profile.go
+++ b/internal/profile/profile.go
@@ -271,6 +271,13 @@ func RedactText(value string) string {
 	return credentialPattern.ReplaceAllString(value, `${1}${2}:REDACTED@`)
 }
 
+// RedactUserinfoText removes usernames as well as passwords. Form frames use
+// this stricter boundary because even the identity of the probe source is
+// private while a Profile is being edited.
+func RedactUserinfoText(value string) string {
+	return credentialPattern.ReplaceAllString(value, `${1}REDACTED@`)
+}
+
 func ObscureURL(value string) string {
 	u, err := url.Parse(value)
 	if err != nil || u.User == nil {
@@ -283,9 +290,9 @@ func ObscureURL(value string) string {
 	return u.String()
 }
 
-// ObscureURLForEditing masks only password runes while preserving the input's
+// ObscureURLForEditing masks every userinfo rune while preserving the input's
 // rune count. A text input clone can therefore retain its real cursor and
-// horizontal viewport positions without ever rendering the credential.
+// horizontal viewport positions without rendering either username or password.
 func ObscureURLForEditing(value string) string {
 	matches := credentialPattern.FindAllStringSubmatchIndex(value, -1)
 	if len(matches) == 0 {
@@ -294,10 +301,10 @@ func ObscureURLForEditing(value string) string {
 	var masked strings.Builder
 	last := 0
 	for _, match := range matches {
-		passwordStart, passwordEnd := match[6], match[7]
-		masked.WriteString(value[last:passwordStart])
-		masked.WriteString(strings.Repeat("•", len([]rune(value[passwordStart:passwordEnd]))))
-		last = passwordEnd
+		userinfoStart, userinfoEnd := match[4], match[7]
+		masked.WriteString(value[last:userinfoStart])
+		masked.WriteString(strings.Repeat("•", len([]rune(value[userinfoStart:userinfoEnd]))))
+		last = userinfoEnd
 	}
 	masked.WriteString(value[last:])
 	return masked.String()
diff --git a/internal/tui/foundation_test.go b/internal/tui/foundation_test.go
index fc0fde0..8207e22 100644
--- a/internal/tui/foundation_test.go
+++ b/internal/tui/foundation_test.go
@@ -158,8 +158,14 @@ func TestCompleteModelDefensivelyRedactsEveryRenderedPage(t *testing.T) {
 		if strings.Contains(frame, secret) {
 			t.Fatalf("frame %d exposed a credential:\n%s", i, frame)
 		}
-		if !strings.Contains(frame, redacted) {
-			t.Fatalf("frame %d did not apply the presentation redaction path:\n%s", i, frame)
+		if i < 3 {
+			if !strings.Contains(frame, redacted) {
+				t.Fatalf("frame %d did not apply the presentation redaction path:\n%s", i, frame)
+			}
+			continue
+		}
+		if strings.Contains(frame, "alice") || !strings.Contains(frame, "REDACTED@proxy.example:8443") {
+			t.Fatalf("form frame %d did not mask the entire userinfo:\n%s", i, frame)
 		}
 	}
 }
diff --git a/internal/tui/help_dialog.go b/internal/tui/help_dialog.go
index b63ebc6..f605f6e 100644
--- a/internal/tui/help_dialog.go
+++ b/internal/tui/help_dialog.go
@@ -149,8 +149,8 @@ func (p terminalPresentation) contextualHelp(model presentationState) string {
 			default:
 				body.WriteString("The Single proxy URL field visibly offers Protocol Probe; focus that field and press Ctrl+D to run it explicitly.\n")
 			}
-		} else if model.form.probe.feedback != "" {
-			body.WriteString("The Protocol Probe result remains attached to the generated Advanced Profile URL values.\n")
+		} else if model.form.hasProbeSourceAttachment() {
+			body.WriteString("The Protocol Probe result remains attached to its read-only initiating Single proxy URL context. The HTTP, HTTPS, and ALL/SOCKS values were generated from that probe.\n")
 		}
 	default:
 		body.WriteString(p.theme.section.Render("Dashboard"))
diff --git a/internal/tui/help_dialog_test.go b/internal/tui/help_dialog_test.go
index 521aec8..52f497a 100644
--- a/internal/tui/help_dialog_test.go
+++ b/internal/tui/help_dialog_test.go
@@ -1,6 +1,7 @@
 package tui
 
 import (
+	"context"
 	"fmt"
 	"strings"
 	"testing"
@@ -8,6 +9,7 @@ import (
 	tea "github.com/charmbracelet/bubbletea"
 
 	"proxyctl/internal/app"
+	"proxyctl/internal/probe"
 	"proxyctl/internal/profile"
 )
 
@@ -304,10 +306,6 @@ func TestCompleteModelFooterHintsMatchContextAndAcceptedKeys(t *testing.T) {
 		if probeCommand == nil || !strings.Contains(model.View(), "Protocol Probe in progress") || strings.Contains(model.View(), "Ctrl+D: probe") {
 			t.Fatalf("probe footer did not follow accepted in-field action and progress:\n%s", model.View())
 		}
-		model = updateKey(model, "?")
-		assertUsableFrame(t, model.View(), 80, 24, "Protocol Probe is in progress", "Ctrl+D does not start a duplicate probe")
-		model = updateKey(model, "esc")
-
 		model = updateKey(model, "ctrl+t")
 		if strings.Contains(model.View(), "Ctrl+D: probe") || !strings.Contains(model.View(), "advanced mode") {
 			t.Fatalf("Advanced form advertised a Single-field Protocol Probe:\n%s", model.View())
@@ -335,6 +333,37 @@ func TestCompleteModelFooterHintsMatchContextAndAcceptedKeys(t *testing.T) {
 	})
 }
 
+func TestCompleteModelHelpDocumentsProbeShortcutExplicitOnlyAttachmentAndDuplicateSuppression(t *testing.T) {
+	model := openProtocolProbeEditor(t, &recordingModule{}, func(context.Context, string) (probe.Capabilities, error) {
+		return probe.Capabilities{HTTP: true, SOCKS5: true}, nil
+	}, "proxy.example:7890")
+
+	model = updateKey(model, "?")
+	assertUsableFrame(t, model.View(), 80, 24,
+		"Ctrl+D explicitly runs Protocol Probe for the focused Single proxy URL field.",
+		"never runs on form entry, focus changes, or save.")
+	model = updateKey(model, "esc")
+
+	model, command := startProtocolProbe(t, model)
+	updated, duplicate := model.Update(tea.KeyMsg{Type: tea.KeyCtrlD})
+	model = updated.(Model)
+	if duplicate != nil {
+		t.Fatal("repeated Probe shortcut emitted duplicate work")
+	}
+	model = updateKey(model, "?")
+	assertUsableFrame(t, model.View(), 80, 24,
+		"Protocol Probe is in progress for the Single proxy URL field.",
+		"Ctrl+D does not start a duplicate probe")
+	model = updateKey(model, "esc")
+
+	model = finishProtocolProbe(t, model, command)
+	model = updateKey(model, "?")
+	assertUsableFrame(t, model.View(), 80, 24,
+		"The Protocol Probe result remains attached to its read-only initiating Single",
+		"proxy URL context. The HTTP, HTTPS, and ALL/SOCKS values were generated from",
+		"that probe.")
+}
+
 func TestCompleteModelHelpOverEditorPreservesFieldCursorPreviewAndResizeState(t *testing.T) {
 	module := &profileManagementModule{}
 	model := openNewProfileEditor(t, module)
diff --git a/internal/tui/model.go b/internal/tui/model.go
index 3a1e39a..1c284d3 100644
--- a/internal/tui/model.go
+++ b/internal/tui/model.go
@@ -2,9 +2,7 @@ package tui
 
 import (
 	"context"
-	"errors"
 	"fmt"
-	"strings"
 
 	tea "github.com/charmbracelet/bubbletea"
 
@@ -47,14 +45,12 @@ type Model struct {
 	detect                  func(context.Context, string) (probe.Capabilities, error)
 }
 
-// probeDone carries one finished Protocol Probe back to the form. Endpoint and
-// input text deliberately stay in formState: an asynchronous result cannot
-// introduce userinfo into status, and formID plus generation reject stale work.
+// probeDone carries only detector output and formState's opaque typed token.
+// Source data and all validation/application rules remain owned by formState.
 type probeDone struct {
-	caps       probe.Capabilities
-	err        error
-	formID     uint64
-	generation uint64
+	caps  probe.Capabilities
+	err   error
+	token probeToken
 }
 
 type profileDeleteConfirmation struct {
@@ -177,57 +173,7 @@ func (m Model) Update(message tea.Msg) (tea.Model, tea.Cmd) {
 		return m, waitForOperation(progress.updates)
 	}
 	if done, ok := message.(probeDone); ok {
-		if m.page != formPage || !m.form.probe.active || done.formID != m.form.id || done.generation != m.form.probe.generation {
-			return m, nil
-		}
-		m.form.probe.active = false
-		address := m.form.probe.address
-		switch {
-		case done.err != nil:
-			// Detector errors are intentionally not rendered. Production errors are
-			// based on the credential-free dial endpoint, but this boundary also
-			// protects frames if a lower layer returns hostile credential text.
-			m.form.probe.feedback = "Protocol Probe failed for " + address
-		case !done.caps.HTTP && !done.caps.SOCKS5:
-			m.form.probe.feedback = "Protocol Probe: unrecognized protocol at " + address
-		default:
-			raw := m.form.profile.SingleURL
-			if done.caps.HTTP && done.caps.SOCKS5 {
-				httpURL, err := probe.URL(raw, probe.Capabilities{HTTP: true})
-				if err != nil {
-					m.form.probe.feedback = "Protocol Probe could not apply the detected capabilities"
-					return m, nil
-				}
-				socksURL, err := probe.URL(raw, probe.Capabilities{SOCKS5: true})
-				if err != nil {
-					m.form.probe.feedback = "Protocol Probe could not apply the detected capabilities"
-					return m, nil
-				}
-				m.form.profile.Mode = profile.AdvancedMode
-				m.form.profile.HTTPURL = httpURL
-				m.form.profile.HTTPSURL = httpURL
-				m.form.profile.AllURL = strings.Replace(socksURL, "socks5h://", "socks5://", 1)
-				m.form.advancedInitialized = true
-				m.form.probe.field = profile.HTTPURLField
-				m.form.probe.feedback = "Protocol Probe: detected HTTP and SOCKS5 proxy at " + address
-				m.form.rebuildInputs(1)
-				return m, nil
-			}
-			rewritten, err := probe.URL(raw, done.caps)
-			if err != nil {
-				m.form.probe.feedback = "Protocol Probe could not apply the detected capabilities"
-				return m, nil
-			}
-			m.form.profile.SingleURL = rewritten
-			m.form.probe.field = profile.SingleURLField
-			kind := "SOCKS5"
-			if done.caps.HTTP {
-				kind = "HTTP"
-			}
-			m.form.probe.feedback = "Protocol Probe: detected " + kind + " proxy at " + address
-			m.form.rebuildInputs(1)
-		}
-		return m, nil
+		return m, m.form.applyProbeResult(done.token, done.caps, done.err)
 	}
 	key, ok := message.(tea.KeyMsg)
 	if !ok {
@@ -596,26 +542,14 @@ func (m Model) updateForm(key tea.KeyMsg) (tea.Model, tea.Cmd) {
 		m.form = formState{}
 		return m, nil
 	case tea.KeyCtrlD:
-		if m.form.profile.Mode != profile.SingleMode || m.form.currentField() != profile.SingleURLField || m.form.probe.active {
+		address, token, started := m.form.startProbe()
+		if !started {
 			return m, nil
 		}
-		m.form.syncFocusedValue()
-		m.form.invalidateProbe()
-		m.form.probe.field = profile.SingleURLField
-		address, err := probeAddress(m.form.profile.SingleURL)
-		if err != nil {
-			m.form.probe.feedback = "Protocol Probe: " + err.Error()
-			return m, nil
-		}
-		m.form.probe.active = true
-		m.form.probe.address = address
-		m.form.probe.feedback = "Protocol Probe: checking " + address + "…"
 		detect := m.detect
-		formID := m.form.id
-		generation := m.form.probe.generation
 		return m, func() tea.Msg {
 			caps, err := detect(context.Background(), address)
-			return probeDone{caps: caps, err: err, formID: formID, generation: generation}
+			return probeDone{caps: caps, err: err, token: token}
 		}
 	case tea.KeyCtrlT:
 		return m, m.form.toggleMode()
@@ -653,17 +587,6 @@ func (m *Model) applyProfileMutation(intent app.Intent, preferredName string) ap
 	return result
 }
 
-// probeAddress extracts a bare host:port from the typed endpoint for dialing
-// and status text, dropping any userinfo so credentials are never displayed
-// or sent anywhere.
-func probeAddress(raw string) (string, error) {
-	u, err := profile.ParseProxyURL(raw)
-	if err != nil {
-		return "", errors.New("Single proxy URL must include host:port")
-	}
-	return u.Host, nil
-}
-
 func (m Model) selectedProfile() (profile.Profile, bool) {
 	if m.selectedProfileName != "" {
 		for i := range m.snapshot.Profiles {
diff --git a/internal/tui/model_test.go b/internal/tui/model_test.go
index 335bf2e..41135d1 100644
--- a/internal/tui/model_test.go
+++ b/internal/tui/model_test.go
@@ -1,15 +1,12 @@
 package tui
 
 import (
-	"context"
-	"errors"
 	"strings"
 	"testing"
 
 	tea "github.com/charmbracelet/bubbletea"
 
 	"proxyctl/internal/app"
-	"proxyctl/internal/probe"
 	"proxyctl/internal/profile"
 )
 
@@ -138,349 +135,6 @@ func TestNoProfileStateStaysOnAccessibleMainPage(t *testing.T) {
 	}
 }
 
-func TestProtocolProbeDetectsHTTPAndRewritesSingleURL(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	var probed []string
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		probed = append(probed, address)
-		return probe.Capabilities{HTTP: true}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "alice:secret@localhost:8888")
-
-	model, cmd := pressCtrlD(model)
-	if cmd == nil {
-		t.Fatal("ctrl+d did not start a Protocol Probe")
-	}
-	updated, _ := model.Update(cmd())
-	model = updated.(Model)
-
-	if len(probed) != 1 || probed[0] != "localhost:8888" {
-		t.Fatalf("Protocol Probe dialed %#v, want exactly localhost:8888 without userinfo", probed)
-	}
-	if got := model.form.profile.SingleURL; got != "http://alice:secret@localhost:8888" {
-		t.Fatalf("Single URL after probe = %q, want detected scheme with preserved userinfo", got)
-	}
-	view := model.View()
-	if !strings.Contains(view, "Protocol Probe: detected HTTP proxy at localhost:8888") {
-		t.Fatalf("form view missing detection status:\n%s", view)
-	}
-	if strings.Contains(view, "secret") {
-		t.Fatalf("form view exposed proxy password:\n%s", view)
-	}
-}
-
-func pressCtrlD(model Model) (Model, tea.Cmd) {
-	updated, cmd := model.Update(tea.KeyMsg{Type: tea.KeyCtrlD})
-	return updated.(Model), cmd
-}
-
-func TestProtocolProbeFailureLeavesFieldUntouchedAndSavePossible(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		return probe.Capabilities{}, errors.New("connection refused")
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:8888")
-
-	model, cmd := pressCtrlD(model)
-	if cmd == nil {
-		t.Fatal("ctrl+d did not start a Protocol Probe")
-	}
-	updated, _ := model.Update(cmd())
-	model = updated.(Model)
-
-	if got := model.form.profile.SingleURL; got != "localhost:8888" {
-		t.Fatalf("failed probe rewrote Single URL to %q", got)
-	}
-	if view := model.View(); !strings.Contains(view, "Protocol Probe failed for localhost:8888") || strings.Contains(view, "connection refused") {
-		t.Fatalf("form view missing credential-safe field failure status:\n%s", view)
-	}
-	model = updateKey(model, "ctrl+s")
-	if len(module.intents) != 1 || module.intents[0].Kind != app.CreateProfile {
-		t.Fatalf("save after failed probe dispatched %#v", module.intents)
-	}
-}
-
-func TestProtocolProbeUnrecognizedProtocolLeavesFieldUntouched(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		return probe.Capabilities{}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:8888")
-
-	model, cmd := pressCtrlD(model)
-	if cmd == nil {
-		t.Fatal("ctrl+d did not start a Protocol Probe")
-	}
-	updated, _ := model.Update(cmd())
-	model = updated.(Model)
-
-	if got := model.form.profile.SingleURL; got != "localhost:8888" {
-		t.Fatalf("unrecognized probe rewrote Single URL to %q", got)
-	}
-	if view := model.View(); !strings.Contains(view, "Protocol Probe: unrecognized protocol at localhost:8888") {
-		t.Fatalf("form view missing unrecognized status:\n%s", view)
-	}
-}
-
-func TestProtocolProbeIgnoresRepeatedCtrlDWhileInFlight(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	calls := 0
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		calls++
-		return probe.Capabilities{HTTP: true}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:8888")
-
-	model, first := pressCtrlD(model)
-	if first == nil {
-		t.Fatal("ctrl+d did not start a Protocol Probe")
-	}
-	model, second := pressCtrlD(model)
-	if second != nil {
-		t.Fatal("ctrl+d during an in-flight probe started a second one")
-	}
-	updated, _ := model.Update(first())
-	model = updated.(Model)
-
-	if calls != 1 {
-		t.Fatalf("probe ran %d times, want 1", calls)
-	}
-	if got := model.form.profile.SingleURL; got != "http://localhost:8888" {
-		t.Fatalf("Single URL after probe = %q", got)
-	}
-}
-
-func TestProtocolProbeLateResultIgnoredAfterEscLeavesForm(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		return probe.Capabilities{HTTP: true}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:8888")
-
-	model, cmd := pressCtrlD(model)
-	if cmd == nil {
-		t.Fatal("ctrl+d did not start a Protocol Probe")
-	}
-	model = updateKey(model, "esc")
-	updated, _ := model.Update(cmd())
-	model = updated.(Model)
-
-	if model.page != profilesPage {
-		t.Fatalf("page = %d, want profilesPage", model.page)
-	}
-	if strings.Contains(model.status, "detected HTTP proxy") {
-		t.Fatalf("profiles page status mutated by late probe result: %s", model.status)
-	}
-	if model.form.profile.SingleURL != "" {
-		t.Fatalf("abandoned form SingleURL mutated to %q", model.form.profile.SingleURL)
-	}
-}
-
-func TestProtocolProbeLateResultIgnoredAfterSaveLeavesForm(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		return probe.Capabilities{HTTP: true}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:8888")
-
-	model, cmd := pressCtrlD(model)
-	if cmd == nil {
-		t.Fatal("ctrl+d did not start a Protocol Probe")
-	}
-	model = updateKey(model, "ctrl+s")
-	if len(module.intents) != 1 {
-		t.Fatalf("save dispatched %d intents, want 1", len(module.intents))
-	}
-
-	updated, _ := model.Update(cmd())
-	model = updated.(Model)
-
-	if model.page != profilesPage {
-		t.Fatalf("page = %d, want profilesPage", model.page)
-	}
-	if strings.Contains(model.status, "detected HTTP proxy") {
-		t.Fatalf("profiles page status mutated by late probe result: %s", model.status)
-	}
-	if model.form.profile.SingleURL != "" {
-		t.Fatalf("abandoned form SingleURL mutated to %q", model.form.profile.SingleURL)
-	}
-}
-
-func TestSaveFormDoesNotTriggerProtocolProbe(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	calls := 0
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		calls++
-		return probe.Capabilities{HTTP: true}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:8888")
-
-	model = updateKey(model, "ctrl+s")
-	if calls != 0 {
-		t.Fatalf("ctrl+s triggered %d probe call(s), want 0", calls)
-	}
-	if len(module.intents) != 1 || module.intents[0].Kind != app.CreateProfile {
-		t.Fatalf("ctrl+s dispatched %#v", module.intents)
-	}
-}
-
-func TestProtocolProbeOnlyTriggersOnSingleURLField(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	calls := 0
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		calls++
-		return probe.Capabilities{HTTP: true}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-
-	// Field 0 is Name.
-	model, cmd := pressCtrlD(model)
-	if cmd != nil {
-		t.Fatal("ctrl+d on Name field started a Protocol Probe")
-	}
-
-	// Move to Single URL and probe once so we can reach the Bypass field.
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:8888")
-	model, cmd = pressCtrlD(model)
-	if cmd == nil {
-		t.Fatal("ctrl+d on Single URL field did not start a Protocol Probe")
-	}
-	updated, _ := model.Update(cmd())
-	model = updated.(Model)
-
-	// Move to Bypass (field 2) and press Ctrl+D again.
-	model = updateKey(model, "tab")
-	model, cmd = pressCtrlD(model)
-	if cmd != nil {
-		t.Fatal("ctrl+d on Bypass field started a Protocol Probe")
-	}
-
-	if calls != 1 {
-		t.Fatalf("Protocol Probe ran %d times, want 1", calls)
-	}
-}
-
-func TestProtocolProbeDetectsDualProtocolEndpointBuildsCompatibleAdvancedProfile(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		return probe.Capabilities{HTTP: true, SOCKS5: true}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:7890")
-
-	model, cmd := pressCtrlD(model)
-	if cmd == nil {
-		t.Fatal("ctrl+d did not start a Protocol Probe")
-	}
-	updated, _ := model.Update(cmd())
-	model = updated.(Model)
-
-	got := model.form.profile
-	if got.Mode != profile.AdvancedMode || got.HTTPURL != "http://localhost:7890" || got.HTTPSURL != "http://localhost:7890" || got.AllURL != "socks5://localhost:7890" {
-		t.Fatalf("dual-protocol Profile = %#v", got)
-	}
-	if view := model.View(); !strings.Contains(view, "Protocol Probe: detected HTTP and SOCKS5 proxy at localhost:7890") {
-		t.Fatalf("form view missing dual-protocol detection status:\n%s", view)
-	}
-}
-
-func TestProtocolProbeDetectsSOCKS5AndRewritesSingleURL(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		return probe.Capabilities{SOCKS5: true}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:8888")
-
-	model, cmd := pressCtrlD(model)
-	if cmd == nil {
-		t.Fatal("ctrl+d did not start a Protocol Probe")
-	}
-	updated, _ := model.Update(cmd())
-	model = updated.(Model)
-
-	if got := model.form.profile.SingleURL; got != "socks5h://localhost:8888" {
-		t.Fatalf("Single URL after SOCKS5 probe = %q, want socks5h://localhost:8888", got)
-	}
-	if view := model.View(); !strings.Contains(view, "Protocol Probe: detected SOCKS5 proxy at localhost:8888") {
-		t.Fatalf("form view missing SOCKS5 detection status:\n%s", view)
-	}
-}
-
-func TestProtocolProbeInAdvancedModeShowsHintWithoutProbing(t *testing.T) {
-	module := &recordingModule{}
-	model := NewModel(module)
-	calls := 0
-	model.detect = func(_ context.Context, address string) (probe.Capabilities, error) {
-		calls++
-		return probe.Capabilities{HTTP: true}, nil
-	}
-	model = updateKey(model, "m")
-	model = updateKey(model, "n")
-	model = updateRunes(model, "home")
-	model = updateKey(model, "ctrl+t")
-	model = updateKey(model, "tab")
-	model = updateRunes(model, "localhost:8888")
-
-	model, cmd := pressCtrlD(model)
-	if cmd != nil {
-		t.Fatal("ctrl+d in Advanced mode started a Protocol Probe")
-	}
-	if calls != 0 {
-		t.Fatalf("Advanced mode probe ran %d times, want 0", calls)
-	}
-	if view := model.View(); strings.Contains(view, "Protocol Probe") || strings.Contains(view, "Ctrl+D") {
-		t.Fatalf("Advanced mode advertised an inapplicable Protocol Probe action:\n%s", view)
-	}
-}
-
 func updateKey(model Model, key string) Model {
 	msg := tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune(key)}
 	special := map[string]tea.KeyType{
diff --git a/internal/tui/pages.go b/internal/tui/pages.go
index 0853485..c4466a8 100644
--- a/internal/tui/pages.go
+++ b/internal/tui/pages.go
@@ -238,6 +238,12 @@ func (p terminalPresentation) formView(model presentationState) terminalPage {
 			fmt.Fprintf(&fields, "\n    %s", probeText)
 			currentLine++
 		}
+		if item.field == profile.NameField && model.form.hasProbeSourceAttachment() {
+			fmt.Fprintf(&fields, "\n  Single proxy URL probe [read-only]: %s", profile.ObscureURLForEditing(model.form.probe.sourceValue))
+			fmt.Fprintf(&fields, "\n    %s", model.form.probe.feedback)
+			fields.WriteString("\n    Generated Advanced URL fields from this Single proxy URL probe:")
+			currentLine += 3
+		}
 		validation := model.form.validationText(i)
 		if item.field == profile.NameField {
 			if conflict := model.form.nameConflict(model.snapshot.Profiles); conflict != "" {
diff --git a/internal/tui/presentation.go b/internal/tui/presentation.go
index dc644a6..1d9f3ac 100644
--- a/internal/tui/presentation.go
+++ b/internal/tui/presentation.go
@@ -146,8 +146,13 @@ func (p terminalPresentation) Render(state presentationState) string {
 	page = redactTerminalPage(page)
 	// Dashboard composition retains structured Target metadata until pane sizes
 	// are known. Redact the fully composed frame as the final presentation
-	// boundary as well, so no render path can bypass credential scrubbing.
-	return profile.RedactText(p.renderShell(page, width, height))
+	// boundary as well, so no render path can bypass credential scrubbing. Form
+	// frames use the stricter boundary that removes the entire userinfo.
+	frame := p.renderShell(page, width, height)
+	if state.page == formPage {
+		return profile.RedactUserinfoText(frame)
+	}
+	return profile.RedactText(frame)
 }
 
 func renderStatus(state presentationState) string {
diff --git a/internal/tui/profile_editor_test.go b/internal/tui/profile_editor_test.go
index 64d82e7..2603506 100644
--- a/internal/tui/profile_editor_test.go
+++ b/internal/tui/profile_editor_test.go
@@ -55,26 +55,34 @@ func TestCompleteModelProfileEditorSupportsCursorEditingDeletionAndPaste(t *test
 	}
 }
 
-func TestCompleteModelProfileEditorHorizontallyScrollsLongSecretURLWithoutDisclosure(t *testing.T) {
+func TestCompleteModelProfileEditorMasksEntireUserinfoWhilePreservingScrollAndSavedValue(t *testing.T) {
 	module := &profileManagementModule{}
 	model := openNewProfileEditor(t, module)
 	model = updateRunes(model, "office")
 	model = updateKey(model, "tab")
+	const username = "operator-private"
 	const secret = "credential-never-rendered"
-	const raw = "https://operator:" + secret + "@this-is-a-very-long-proxy-hostname-for-horizontal-scroll.example:8443"
+	const raw = "https://" + username + ":" + secret + "@this-is-a-very-long-proxy-hostname-for-horizontal-scroll.example:8443"
 	model = updateRunes(model, raw)
 
 	end := model.View()
 	assertUsableFrame(t, end, 80, 24, "[focused]", "scroll.example:8443")
-	if strings.Contains(end, secret) || strings.Contains(end, "https://operator") {
-		t.Fatalf("end-scrolled input disclosed credentials or failed to scroll:\n%s", end)
+	for _, literal := range []string{username, secret} {
+		if strings.Contains(end, literal) {
+			t.Fatalf("end-scrolled input disclosed userinfo %q:\n%s", literal, end)
+		}
 	}
 
 	model = editorKey(model, tea.KeyHome)
 	start := model.View()
-	assertUsableFrame(t, start, 80, 24, "https://operator:")
-	if strings.Contains(start, secret) || strings.Contains(start, "scroll.example:8443") {
-		t.Fatalf("home did not scroll to the safe beginning of the input:\n%s", start)
+	assertUsableFrame(t, start, 80, 24, "https://")
+	if strings.Contains(start, username) || strings.Contains(start, secret) || strings.Contains(start, "scroll.example:8443") {
+		t.Fatalf("home did not scroll to the masked beginning of the input:\n%s", start)
+	}
+
+	model = updateKey(model, "ctrl+s")
+	if len(module.intents) != 1 || module.intents[0].Profile.SingleURL != raw {
+		t.Fatalf("editable masking changed saved Profile semantics: %#v", module.intents)
 	}
 }
 
diff --git a/internal/tui/profile_form.go b/internal/tui/profile_form.go
index 6fbe682..645d1cb 100644
--- a/internal/tui/profile_form.go
+++ b/internal/tui/profile_form.go
@@ -1,12 +1,14 @@
 package tui
 
 import (
+	"errors"
 	"fmt"
 	"strings"
 
 	"github.com/charmbracelet/bubbles/textinput"
 	tea "github.com/charmbracelet/bubbletea"
 
+	"proxyctl/internal/probe"
 	"proxyctl/internal/profile"
 )
 
@@ -22,12 +24,19 @@ type formDefinition struct {
 	value string
 }
 
-type protocolProbeFieldState struct {
-	active     bool
+type probeToken struct {
+	formID     uint64
 	generation uint64
-	address    string
-	feedback   string
-	field      profile.Field
+	source     profile.Field
+}
+
+type protocolProbeFieldState struct {
+	active         bool
+	token          probeToken
+	address        string
+	feedback       string
+	sourceValue    string
+	sourceAttached bool
 }
 
 type formState struct {
@@ -39,6 +48,7 @@ type formState struct {
 	bypassPreviewLine   int
 	validation          profile.Validation
 	advancedInitialized bool
+	probeGeneration     uint64
 	probe               protocolProbeFieldState
 }
 
@@ -136,7 +146,7 @@ func (f *formState) updateInput(key tea.KeyMsg) tea.Cmd {
 		f.bypassPreviewLine = 0
 		changedField := f.inputs[f.field].field
 		f.syncFocusedValue()
-		if changedField == profile.SingleURLField {
+		if isProxyURLField(changedField) {
 			f.invalidateProbe()
 		}
 		f.refreshValidation()
@@ -195,12 +205,106 @@ func (f formState) currentField() profile.Field {
 	return f.inputs[f.field].field
 }
 
+func isProxyURLField(field profile.Field) bool {
+	switch field {
+	case profile.SingleURLField, profile.HTTPURLField, profile.HTTPSURLField, profile.AllURLField:
+		return true
+	default:
+		return false
+	}
+}
+
 func (f *formState) invalidateProbe() {
-	f.probe.generation++
+	f.probeGeneration++
+	f.probe = protocolProbeFieldState{}
+}
+
+// startProbe owns applicability, duplicate suppression, source capture, and
+// token issuance so callers cannot accidentally start work outside formState's
+// stale-result rules.
+func (f *formState) startProbe() (string, probeToken, bool) {
+	if f.profile.Mode != profile.SingleMode || f.currentField() != profile.SingleURLField || f.probe.active {
+		return "", probeToken{}, false
+	}
+	f.syncFocusedValue()
+	f.invalidateProbe()
+	token := probeToken{formID: f.id, generation: f.probeGeneration, source: profile.SingleURLField}
+	f.probe.token = token
+	f.probe.sourceValue = f.profile.SingleURL
+	address, err := probeAddress(f.probe.sourceValue)
+	if err != nil {
+		f.probe.feedback = "Protocol Probe: " + err.Error()
+		return "", probeToken{}, false
+	}
+	f.probe.active = true
+	f.probe.address = address
+	f.probe.feedback = "Protocol Probe: checking " + address + "…"
+	return address, token, true
+}
+
+// applyProbeResult validates and applies a completion as one form-owned
+// operation. Every stale-result invariant stays here: form identity,
+// generation, source field, active work, mode, and unchanged source value.
+func (f *formState) applyProbeResult(token probeToken, caps probe.Capabilities, resultErr error) tea.Cmd {
+	if !f.probe.active || token != f.probe.token || token.formID != f.id ||
+		token.source != profile.SingleURLField || f.profile.Mode != profile.SingleMode ||
+		f.profile.SingleURL != f.probe.sourceValue {
+		return nil
+	}
 	f.probe.active = false
-	f.probe.address = ""
-	f.probe.feedback = ""
-	f.probe.field = ""
+	address, raw := f.probe.address, f.probe.sourceValue
+	switch {
+	case resultErr != nil:
+		f.probe.feedback = "Protocol Probe failed for " + address
+	case !caps.HTTP && !caps.SOCKS5:
+		f.probe.feedback = "Protocol Probe: unrecognized protocol at " + address
+	case caps.HTTP && caps.SOCKS5:
+		httpURL, err := probe.URL(raw, probe.Capabilities{HTTP: true})
+		if err != nil {
+			f.probe.feedback = "Protocol Probe could not apply the detected capabilities"
+			return nil
+		}
+		socksURL, err := probe.URL(raw, probe.Capabilities{SOCKS5: true})
+		if err != nil {
+			f.probe.feedback = "Protocol Probe could not apply the detected capabilities"
+			return nil
+		}
+		f.profile.Mode = profile.AdvancedMode
+		f.profile.HTTPURL = httpURL
+		f.profile.HTTPSURL = httpURL
+		f.profile.AllURL = strings.Replace(socksURL, "socks5h://", "socks5://", 1)
+		f.advancedInitialized = true
+		f.probe.feedback = "Protocol Probe: detected HTTP and SOCKS5 proxy at " + address
+		f.probe.sourceAttached = true
+		return f.rebuildInputs(1)
+	default:
+		rewritten, err := probe.URL(raw, caps)
+		if err != nil {
+			f.probe.feedback = "Protocol Probe could not apply the detected capabilities"
+			return nil
+		}
+		f.profile.SingleURL = rewritten
+		f.setInputValue(profile.SingleURLField, rewritten)
+		kind := "SOCKS5"
+		if caps.HTTP {
+			kind = "HTTP"
+		}
+		f.probe.feedback = "Protocol Probe: detected " + kind + " proxy at " + address
+	}
+	f.refreshValidation()
+	return nil
+}
+
+func (f *formState) setInputValue(field profile.Field, value string) {
+	for i := range f.inputs {
+		if f.inputs[i].field != field {
+			continue
+		}
+		position := f.inputs[i].input.Position()
+		f.inputs[i].input.SetValue(value)
+		f.inputs[i].input.SetCursor(position)
+		return
+	}
 }
 
 func (f formState) probeText(field profile.Field) string {
@@ -210,12 +314,22 @@ func (f formState) probeText(field profile.Field) string {
 		}
 		return "Protocol Probe [Ctrl+D]: available"
 	}
-	if field == f.probe.field {
-		return f.probe.feedback
-	}
 	return ""
 }
 
+func (f formState) hasProbeSourceAttachment() bool {
+	return f.profile.Mode == profile.AdvancedMode && f.probe.sourceAttached &&
+		f.probe.token.source == profile.SingleURLField && f.probe.feedback != ""
+}
+
+func probeAddress(raw string) (string, error) {
+	u, err := profile.ParseProxyURL(raw)
+	if err != nil {
+		return "", errors.New("Single proxy URL must include host:port")
+	}
+	return u.Host, nil
+}
+
 func (f *formState) scrollBypassPreview(delta int) {
 	if f.currentField() != profile.BypassField {
 		return
diff --git a/internal/tui/protocol_probe_field_action_test.go b/internal/tui/protocol_probe_field_action_test.go
index af6e686..5cbdb85 100644
--- a/internal/tui/protocol_probe_field_action_test.go
+++ b/internal/tui/protocol_probe_field_action_test.go
@@ -105,6 +105,49 @@ func TestCompleteModelProtocolProbeNeverRunsWithoutExplicitInvocation(t *testing
 	}
 }
 
+func TestCompleteModelProtocolProbeCompletionPreservesAnotherEditedFieldsFocusCursorAndViewport(t *testing.T) {
+	module := &recordingModule{}
+	model := openProtocolProbeEditor(t, module, func(context.Context, string) (probe.Capabilities, error) {
+		return probe.Capabilities{HTTP: true}, nil
+	}, "proxy.example:8080")
+	model, command := startProtocolProbe(t, model)
+
+	model = updateKey(model, "shift+tab")
+	model = editorKey(model, tea.KeyHome)
+	model = updateRunes(model, "a-very-long-prefix-that-forces-the-name-field-to-scroll-horizontally-")
+	model = editorKey(model, tea.KeyLeft)
+	before := model.View()
+	assertUsableFrame(t, before, 80, 24, "> Name [focused]", "Protocol Probe: checking proxy.example:8080")
+
+	model = finishProtocolProbe(t, model, command)
+	after := model.View()
+	assertUsableFrame(t, after, 80, 24, "> Name [focused]", "Protocol Probe: detected HTTP proxy at proxy.example:8080")
+	if fieldLine(before, "> Name [focused]") != fieldLine(after, "> Name [focused]") {
+		t.Fatalf("non-mode-changing probe completion reset the edited field viewport or cursor:\nbefore:\n%s\nafter:\n%s", before, after)
+	}
+
+	model = updateRunes(model, "X")
+	model = updateKey(model, "ctrl+s")
+	if len(module.intents) != 1 {
+		t.Fatalf("save after asynchronous completion dispatched %#v", module.intents)
+	}
+	if got, want := module.intents[0].Profile.Name, "a-very-long-prefix-that-forces-the-name-field-to-scroll-horizontallyX-office"; got != want {
+		t.Fatalf("focus/cursor was not preserved: saved name = %q, want %q", got, want)
+	}
+	if got := module.intents[0].Profile.SingleURL; got != "http://proxy.example:8080" {
+		t.Fatalf("probe did not update its affected URL input: %q", got)
+	}
+}
+
+func fieldLine(frame, label string) string {
+	for _, line := range strings.Split(frame, "\n") {
+		if strings.Contains(line, label) {
+			return line
+		}
+	}
+	return ""
+}
+
 func TestCompleteModelProtocolProbePopulatesEstablishedCapabilityRepresentations(t *testing.T) {
 	tests := []struct {
 		name string
@@ -143,12 +186,12 @@ func TestCompleteModelProtocolProbePopulatesEstablishedCapabilityRepresentations
 			}
 			attachedField := "Single proxy URL"
 			if test.caps.HTTP && test.caps.SOCKS5 {
-				attachedField = "HTTP URL"
+				attachedField = "Single proxy URL probe [read-only]"
 			}
 			field := strings.Index(view, attachedField)
 			result := strings.Index(view, "Protocol Probe: detected")
 			if field < 0 || result < field || strings.Count(view[field:result], "\n") > 1 {
-				t.Fatalf("capability result was not attached to its populated URL field:\n%s", view)
+				t.Fatalf("capability result was not attached to its initiating URL context:\n%s", view)
 			}
 
 			model = updateKey(model, "ctrl+s")
@@ -163,6 +206,27 @@ func TestCompleteModelProtocolProbePopulatesEstablishedCapabilityRepresentations
 	}
 }
 
+func TestCompleteModelProtocolProbeDualResultRetainsSingleSourceAndLinksGeneratedFields(t *testing.T) {
+	model := openProtocolProbeEditor(t, &recordingModule{}, func(context.Context, string) (probe.Capabilities, error) {
+		return probe.Capabilities{HTTP: true, SOCKS5: true}, nil
+	}, "proxy.example:7890")
+	model, command := startProtocolProbe(t, model)
+	model = finishProtocolProbe(t, model, command)
+	view := model.View()
+	assertUsableFrame(t, view, 80, 24,
+		"Create Proxy Profile — advanced mode",
+		"Single proxy URL probe [read-only]: proxy.example:7890",
+		"Protocol Probe: detected HTTP and SOCKS5 proxy at proxy.example:7890",
+		"Generated Advanced URL fields from this Single proxy URL probe:",
+		"HTTP URL", "HTTPS URL", "ALL/SOCKS URL")
+	if strings.Index(view, "Single proxy URL probe [read-only]") > strings.Index(view, "HTTP URL") {
+		t.Fatalf("initiating Single URL context was not visibly linked before generated fields:\n%s", view)
+	}
+	if strings.Contains(fieldLine(view, "HTTP URL"), "Protocol Probe") {
+		t.Fatalf("dual result was silently relabelled as an HTTP-field probe:\n%s", view)
+	}
+}
+
 func TestCompleteModelProtocolProbeFailureAndUnrecognizedResultsRemainEditableAndSavable(t *testing.T) {
 	tests := []struct {
 		name string
@@ -338,33 +402,43 @@ func TestCompleteModelProtocolProbeSurvivesResizeWithoutRestartingOrDetaching(t
 	}
 }
 
-func TestCompleteModelProtocolProbeKeepsCredentialsOutOfDialStatusErrorsAndFrames(t *testing.T) {
+func TestCompleteModelProtocolProbeKeepsAllUserinfoOutOfDialStatusErrorsAndEveryFormFrame(t *testing.T) {
 	const (
+		inputUser   = "alice-private"
 		inputSecret = "input-secret"
+		errorUser   = "mallory-private"
 		errorSecret = "error-secret"
 	)
 	var dialed []string
-	model := openProtocolProbeEditor(t, &recordingModule{}, func(_ context.Context, address string) (probe.Capabilities, error) {
+	module := &recordingModule{}
+	model := openProtocolProbeEditor(t, module, func(_ context.Context, address string) (probe.Capabilities, error) {
 		dialed = append(dialed, address)
-		return probe.Capabilities{}, errors.New("failed https://mallory:" + errorSecret + "@evil.example:9999")
-	}, "alice:"+inputSecret+"@proxy.example:8080")
+		return probe.Capabilities{}, errors.New("failed https://" + errorUser + ":" + errorSecret + "@evil.example:9999")
+	}, inputUser+":"+inputSecret+"@proxy.example:8080")
+	frames := []string{model.View()}
 	model, command := startProtocolProbe(t, model)
-	progress := model.View()
-	if strings.Contains(progress, inputSecret) {
-		t.Fatalf("probe progress exposed credentials:\n%s", progress)
-	}
-	for _, line := range strings.Split(progress, "\n") {
-		if strings.Contains(line, "Protocol Probe") && strings.Contains(line, "alice") {
-			t.Fatalf("probe-generated progress exposed userinfo:\n%s", progress)
-		}
-	}
+	frames = append(frames, model.View())
 	model = finishProtocolProbe(t, model, command)
-	view := model.View()
+	frames = append(frames, model.View())
+	model = resize(model, 60, 16)
+	frames = append(frames, model.View())
+	model = resize(model, 80, 24)
+	frames = append(frames, model.View())
+
 	if len(dialed) != 1 || dialed[0] != "proxy.example:8080" {
 		t.Fatalf("probe dial evidence = %#v, want credential-free endpoint", dialed)
 	}
-	if strings.Contains(view, inputSecret) || strings.Contains(view, errorSecret) || strings.Contains(view, "mallory") {
-		t.Fatalf("probe frame exposed input or lower-layer credentials:\n%s", view)
+	for i, frame := range frames {
+		for _, literal := range []string{inputUser, inputSecret, errorUser, errorSecret} {
+			if strings.Contains(frame, literal) {
+				t.Fatalf("form frame %d exposed userinfo literal %q:\n%s", i, literal, frame)
+			}
+		}
+	}
+	assertUsableFrame(t, frames[len(frames)-1], 80, 24, "Protocol Probe failed for proxy.example:8080")
+
+	model = updateKey(model, "ctrl+s")
+	if len(module.intents) != 1 || module.intents[0].Profile.SingleURL != "http://"+inputUser+":"+inputSecret+"@proxy.example:8080" {
+		t.Fatalf("userinfo masking weakened saved Profile semantics: %#v", module.intents)
 	}
-	assertUsableFrame(t, view, 80, 24, "Protocol Probe failed for proxy.example:8080")
 }