Show amounts for OP_RETURN outputs

ports/stm32/boards/Passport/modules/flows/sign_psbt_common_flow.py

@@ -201,7 +201,9 @@ def render_output(self, o):
         dest = self.chain.render_address(o.scriptPubKey)
 
         if dest.startswith("OP_RETURN"):
-            return '\n{}\n{}'.format(
+            return '\n{}\n{}\n\n{}\n{}'.format(
+                recolor(HIGHLIGHT_TEXT_HEX, 'Amount'),
+                val,
                 recolor(HIGHLIGHT_TEXT_HEX, 'Message'),
                 dest.split('\n', 1)[1])  # user-defined message starts after "OP_RETURN:\n"
 

ports/stm32/boards/Passport/modules/tests/test_unit.py

@@ -24,5 +24,9 @@ def test_ui(test):
     assert test('ui.py') == b'OK'
 
 
+def test_sign_psbt(test):
+    assert test('sign_psbt.py') == b'OK'
+
+
 def test_foundation(test):
     assert test('foundation.py') == b'OK'

ports/stm32/boards/Passport/modules/tests/unit/sign_psbt.py

@@ -0,0 +1,42 @@
+# SPDX-FileCopyrightText: 2026 Foundation Devices, Inc. <hello@foundation.xyz>
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# Test trusted-display rendering for PSBT outputs.
+
+from flows.sign_psbt_common_flow import SignPsbtCommonFlow
+
+
+class FakeChain:
+    def render_value(self, value):
+        return (str(value), 'sats')
+
+    def render_address(self, script):
+        return 'OP_RETURN:\n{}'.format(script)
+
+
+class FakeFlow:
+    chain = FakeChain()
+
+
+class FakeOutput:
+    def __init__(self, value, message):
+        self.nValue = value
+        self.scriptPubKey = message
+
+
+def assert_op_return_output(value, message):
+    rendered = SignPsbtCommonFlow.render_output(FakeFlow(), FakeOutput(value, message))
+
+    amount_label = rendered.find('Amount')
+    amount = rendered.find('{} sats'.format(value))
+    message_label = rendered.find('Message')
+    payload = rendered.find(message)
+
+    assert -1 not in (amount_label, amount, message_label, payload)
+    assert amount_label < amount < message_label < payload
+
+
+assert_op_return_output(0, 'zero-value-message')
+assert_op_return_output(50000000, 'payment-id-12345')
+
+return_value.write(b'OK')