diff --git a/capa/features/extractors/ida/insn.py b/capa/features/extractors/ida/insn.py
index c180c2fa..6440164b 100644
--- a/capa/features/extractors/ida/insn.py
+++ b/capa/features/extractors/ida/insn.py
@@ -149,6 +149,9 @@ def extract_insn_offset_features(f, bb, insn):
             #   mov esi, dword_1005B148[esi]
             continue
 
+        # I believe that IDA encodes all offsets as two's complement in a u32.
+        # a 64-bit displacement isn't a thing, see:
+        # https://stackoverflow.com/questions/31853189/x86-64-assembly-why-displacement-not-64-bits
         op_off = capa.features.extractors.helpers.twos_complement(op_off, 32)
 
         yield Offset(op_off), insn.ea
diff --git a/tests/test_ida_features.py b/tests/test_ida_features.py
index 6c967937..562158f1 100644
--- a/tests/test_ida_features.py
+++ b/tests/test_ida_features.py
@@ -273,7 +273,7 @@ def test_basic_block_count():
 if __name__ == "__main__":
     print("-" * 80)
 
-    # invoke all functions in this module that start with `parse_`
+    # invoke all functions in this module that start with `test_`
     for name in dir(sys.modules[__name__]):
         if not name.startswith("test_"):
             continue