show effective seed in View Seed Words

### releases/Next-ChangeLog.md
@@ -23,6 +23,7 @@ This lists the new changes that have not yet been published in a normal release.
   download (signed txn, visualization, backup), require an encrypted session,
   and are invalidated by any upload, newly staged transaction, or new session.
   Thanks to [@drk1wi](https://github.com/drk1wi).
+- Change: When a BIP-39 passphrase is active, View Seed Words now shows only the effective extended private key instead of the underlying seed words.
 
 # Mk Specific Changes
 

### shared/actions.py
@@ -613,7 +613,7 @@ async def clear_seed(*a):
 
 def render_master_secrets(mode, raw, node):
     # Render list of words, or XPRV / master secret to text.
-    import stash, chains
+    import chains
 
     c = chains.current_chain()
     qr_alnum = False
@@ -635,12 +635,6 @@ def render_master_secrets(mode, raw, node):
 
         msg += ux_render_words(words)
 
-        if stash.bip39_passphrase:
-            msg += '\n\nBIP-39 Passphrase:\n    *****'
-            if node:
-                msg += '\n\nSeed+Passphrase:\n%s' % c.serialize_private(node)
-
-
     elif mode == 'xprv':
         title = "Extended Private Key" if version.has_qwerty else None
         msg = c.serialize_private(node)
@@ -657,36 +651,29 @@ def render_master_secrets(mode, raw, node):
     return title, msg, qr, qr_alnum
 
 async def view_seed_words(*a):
-    if not await ux_confirm('The next screen will show the seed words'
-                            ' (and if defined, your BIP-39 passphrase).'
-                            '\n\nAnyone with knowledge of those words '
+    if not await ux_confirm('The next screen will show the secret seed words'
+                            ' (or extended private key).'
+                            '\n\nAnyone with knowledge of the secret '
                             'can control all funds in this wallet.'):
         return
 
     import stash
     from glob import dis, NFC
 
     dis.fullscreen("Wait...")
-    dis.busy_bar(True)
 
-    # preserve old UI where we show words + passphrase
-    # instead of just calculated seed + passphrase = extended privkey
-    # new: calculated xprv is now also shown for BIP39 passphrase wallet
-    raw = mode = None
-    if stash.bip39_passphrase:
-        # get main secret - bypass tmp
-        with stash.SensitiveValues(bypass_tmp=True, enforce_delta=True) as sv:
-            assert sv.mode == "words"
-            raw = sv.raw[:]
-            mode = sv.mode
+    # CHANGED: old UI where we show words + passphrase
+    # instead just calculated seed + passphrase = extended privkey for all BIP39 passphrase wallets
 
-        stash.SensitiveValues.clear_cache()
+    with stash.SensitiveValues(enforce_delta=True) as sv:
+        msg = ""
+        if stash.bip39_passphrase:
+            # on the top of the page - so visible on Mk4/5
+            msg += "BIP-39 Passphrase in effect\n\n"
+
+        title, sub_msg, qr, qr_alnum = render_master_secrets(sv.mode, sv.raw, sv.node)
+        msg += sub_msg
 
-    with stash.SensitiveValues(bypass_tmp=False, enforce_delta=True) as sv:
-        dis.busy_bar(False)
-        title, msg, qr, qr_alnum = render_master_secrets(mode or sv.mode,
-                                                         raw or sv.raw,
-                                                         sv.node)
         esc = "1"
         if not version.has_qwerty:
             msg += '\n\nPress (1) to view as QR Code'
@@ -709,7 +696,6 @@ async def view_seed_words(*a):
 
     stash.blank_object(qr)
     stash.blank_object(msg)
-    stash.blank_object(raw)
 
 async def export_seedqr(*a):
     # see standard: <https://github.com/SeedSigner/seedsigner/blob/dev/docs/seed_qr/README.md>

### testing/test_bip39pw.py
@@ -363,7 +363,7 @@ def test_bip39pass_on_ephemeral_seed(generate_ephemeral_words, import_ephemeral_
     enter_complex(passphrase, apply=True)
 
     tmp_seed = Mnemonic.to_seed(" ".join(sec), passphrase=passphrase)
-    tmp_node = BIP32Node.from_master_secret(tmp_seed)
+    tmp_node = BIP32Node.from_master_secret(tmp_seed, netcode="XTN")
     tmp_fp = tmp_node.fingerprint().hex().upper()
 
     time.sleep(.2)
@@ -391,6 +391,24 @@ def test_bip39pass_on_ephemeral_seed(generate_ephemeral_words, import_ephemeral_
         else:
             press_select()  # do not store
 
+    goto_home()
+    pick_menu_item("Advanced/Tools")
+    pick_menu_item("Danger Zone")
+    pick_menu_item("Seed Functions")
+    pick_menu_item("View Seed Words")
+    time.sleep(.1)
+    _, story = cap_story()
+    assert "secret seed words" in story
+    press_select()
+    time.sleep(.1)
+    _, story = cap_story()
+    assert tmp_node.hwif(as_private=True) in story
+    assert story.startswith("BIP-39 Passphrase in effect\n\n")
+    assert passphrase not in story
+    assert "Seed words" not in story
+    press_select()
+    goto_home()
+
     if seed_vault:
         # check correct meta in seed vault
         pick_menu_item("Seed Vault")

### testing/test_ux.py
@@ -493,7 +493,12 @@ def test_show_seed(mode, b39_word, goto_home, pick_menu_item, cap_story, need_ke
     reset_seed_words()
     if mode == 'words':
         set_bip39_pw(b39_word, reset=False)
-        words = simulator_fixed_words.split(" ")
+        if b39_word:
+            seed = Mnemonic.to_seed(simulator_fixed_words, passphrase=b39_word)
+            node = BIP32Node.from_master_secret(seed, netcode="XTN")
+            expect = node.hwif(as_private=True)
+        else:
+            words = simulator_fixed_words.split(" ")
 
     else:
         if b39_word: return
@@ -519,6 +524,8 @@ def test_show_seed(mode, b39_word, goto_home, pick_menu_item, cap_story, need_ke
     title, body = cap_story()
     where = title if is_q1 else body
     assert 'Are you SURE' in where
+    assert 'secret seed words' in body
+    assert 'or extended private key' in body
     assert 'can control all funds' in body
     press_select()      # skip warning
     time.sleep(0.01)
@@ -527,7 +534,7 @@ def test_show_seed(mode, b39_word, goto_home, pick_menu_item, cap_story, need_ke
     if not is_q1:
         assert title == 'NO-TITLE'
 
-    if mode == 'words':
+    if mode == 'words' and not b39_word:
         assert '24' in (title if is_q1 else body)
 
         lines = body.split('\n')
@@ -536,30 +543,18 @@ def test_show_seed(mode, b39_word, goto_home, pick_menu_item, cap_story, need_ke
         else:
             assert lines[1:25] == ['%2d: %s' % (n+1, w) for n,w in enumerate(words)]
 
-        if b39_word:
-            if is_q1:
-                assert lines[9] == 'BIP-39 Passphrase:'
-                assert "*" in lines[10]
-                assert "Seed+Passphrase" in lines[12]
-                ek = lines[13]
-            else:
-                assert lines[26] == 'BIP-39 Passphrase:'
-                assert "*" in lines[27]
-                assert "Seed+Passphrase" in lines[29]
-                ek = lines[30]
-
-            seed = Mnemonic.to_seed(simulator_fixed_words, passphrase=b39_word)
-            expect = BIP32Node.from_master_secret(seed, netcode="XTN")
-            esk = expect.hwif(as_private=True)
-            assert esk == ek
-        else:
-            assert "BIP-39 Passphrase" not in body
-
+        assert "BIP-39 Passphrase" not in body
         qr_expect = ' '.join(w[0:4].upper() for w in words)
 
     else:
         assert expect in body
         qr_expect = expect
+        if b39_word:
+            assert body.startswith("BIP-39 Passphrase in effect\n\n")
+            assert b39_word not in body
+            assert "Seed words" not in body
+        else:
+            assert "BIP-39 Passphrase" not in body
 
     if not is_q1:
         assert '(1) to view as QR Code' in body