diff --git a/core/fpdfapi/font/cpdf_cmap.cpp b/core/fpdfapi/font/cpdf_cmap.cpp
index 0eee5a0..b6e5ead 100644
--- a/core/fpdfapi/font/cpdf_cmap.cpp
+++ b/core/fpdfapi/font/cpdf_cmap.cpp
@@ -361,7 +361,7 @@
 
 uint32_t CPDF_CMap::GetNextChar(ByteStringView pString, size_t* pOffset) const {
   size_t& offset = *pOffset;
-  auto pBytes = pString.raw_span();
+  auto pBytes = pString.unsigned_span();
   switch (m_CodingScheme) {
     case OneByte: {
       return offset < pBytes.size() ? pBytes[offset++] : 0;
diff --git a/core/fpdfapi/page/cpdf_indexedcs.cpp b/core/fpdfapi/page/cpdf_indexedcs.cpp
index 1c0b77b..79ffc5e 100644
--- a/core/fpdfapi/page/cpdf_indexedcs.cpp
+++ b/core/fpdfapi/page/cpdf_indexedcs.cpp
@@ -99,7 +99,7 @@
   }
 
   std::vector<float> comps(m_nBaseComponents);
-  const uint8_t* pTable = m_Table.raw_str();
+  const uint8_t* pTable = m_Table.unsigned_str();
   for (uint32_t i = 0; i < m_nBaseComponents; ++i) {
     comps[i] =
         m_pCompMinMax[i * 2] +
diff --git a/core/fpdfapi/parser/cpdf_crypto_handler.cpp b/core/fpdfapi/parser/cpdf_crypto_handler.cpp
index 61dac42..8d73916 100644
--- a/core/fpdfapi/parser/cpdf_crypto_handler.cpp
+++ b/core/fpdfapi/parser/cpdf_crypto_handler.cpp
@@ -214,7 +214,7 @@
                                        const ByteString& str) {
   BinaryBuffer dest_buf;
   void* context = DecryptStart(objnum, gennum);
-  DecryptStream(context, str.raw_span(), dest_buf);
+  DecryptStream(context, str.unsigned_span(), dest_buf);
   DecryptFinish(context, dest_buf);
   return ByteString(dest_buf.GetSpan());
 }
diff --git a/core/fpdfapi/parser/cpdf_name.cpp b/core/fpdfapi/parser/cpdf_name.cpp
index 6236ef4..37ef20f 100644
--- a/core/fpdfapi/parser/cpdf_name.cpp
+++ b/core/fpdfapi/parser/cpdf_name.cpp
@@ -39,7 +39,7 @@
 }
 
 WideString CPDF_Name::GetUnicodeText() const {
-  return PDF_DecodeText(m_Name.raw_span());
+  return PDF_DecodeText(m_Name.unsigned_span());
 }
 
 bool CPDF_Name::WriteTo(IFX_ArchiveStream* archive,
diff --git a/core/fpdfapi/parser/cpdf_security_handler.cpp b/core/fpdfapi/parser/cpdf_security_handler.cpp
index 3155999..005ebe5 100644
--- a/core/fpdfapi/parser/cpdf_security_handler.cpp
+++ b/core/fpdfapi/parser/cpdf_security_handler.cpp
@@ -38,7 +38,7 @@
   DCHECK_EQ(sizeof(kDefaultPasscode), output.size());
   size_t len = std::min(password.GetLength(), output.size());
   size_t remaining = output.size() - len;
-  FXSYS_memcpy(output.data(), password.raw_str(), len);
+  FXSYS_memcpy(output.data(), password.unsigned_str(), len);
   if (remaining) {
     memcpy(&output[len], kDefaultPasscode, remaining);
   }
@@ -55,11 +55,11 @@
   CRYPT_md5_context md5 = CRYPT_MD5Start();
   CRYPT_MD5Update(&md5, passcode);
   ByteString okey = pEncrypt->GetByteStringFor("O");
-  CRYPT_MD5Update(&md5, okey.raw_span());
+  CRYPT_MD5Update(&md5, okey.unsigned_span());
   uint32_t perm = pEncrypt->GetIntegerFor("P");
   CRYPT_MD5Update(&md5, pdfium::as_bytes(pdfium::span_from_ref(perm)));
   if (!file_id.IsEmpty())
-    CRYPT_MD5Update(&md5, file_id.raw_span());
+    CRYPT_MD5Update(&md5, file_id.unsigned_span());
   const bool is_revision_3_or_greater = pEncrypt->GetIntegerFor("R") >= 3;
   if (!ignore_metadata && is_revision_3_or_greater &&
       !pEncrypt->GetBooleanFor("EncryptMetadata", true)) {
@@ -108,7 +108,7 @@
                     uint8_t* hash) {
   CRYPT_sha2_context sha;
   CRYPT_SHA256Start(&sha);
-  CRYPT_SHA256Update(&sha, password.raw_str(), password.GetLength());
+  CRYPT_SHA256Update(&sha, password.unsigned_str(), password.GetLength());
   CRYPT_SHA256Update(&sha, salt, 8);
   if (vector)
     CRYPT_SHA256Update(&sha, vector, 48);
@@ -133,8 +133,8 @@
     auto encrypted_output_span = pdfium::make_span(encrypted_output);
     DataVector<uint8_t> content;
     for (int j = 0; j < 64; ++j) {
-      content.insert(std::end(content), password.raw_str(),
-                     password.raw_str() + password.GetLength());
+      content.insert(std::end(content), password.unsigned_str(),
+                     password.unsigned_str() + password.GetLength());
       content.insert(std::end(content), input, input + block_size);
       if (vector) {
         content.insert(std::end(content), vector, vector + 48);
@@ -332,18 +332,18 @@
   if (ukey.GetLength() < 48)
     return false;
 
-  const uint8_t* pkey = bOwner ? okey.raw_str() : ukey.raw_str();
+  const uint8_t* pkey = bOwner ? okey.unsigned_str() : ukey.unsigned_str();
   CRYPT_sha2_context sha;
   uint8_t digest[32];
   if (m_Revision >= 6) {
     Revision6_Hash(password, (const uint8_t*)pkey + 32,
-                   bOwner ? ukey.raw_str() : nullptr, digest);
+                   bOwner ? ukey.unsigned_str() : nullptr, digest);
   } else {
     CRYPT_SHA256Start(&sha);
-    CRYPT_SHA256Update(&sha, password.raw_str(), password.GetLength());
+    CRYPT_SHA256Update(&sha, password.unsigned_str(), password.GetLength());
     CRYPT_SHA256Update(&sha, pkey + 32, 8);
     if (bOwner)
-      CRYPT_SHA256Update(&sha, ukey.raw_str(), 48);
+      CRYPT_SHA256Update(&sha, ukey.unsigned_str(), 48);
     CRYPT_SHA256Finish(&sha, digest);
   }
   if (memcmp(digest, pkey, 32) != 0)
@@ -351,13 +351,13 @@
 
   if (m_Revision >= 6) {
     Revision6_Hash(password, (const uint8_t*)pkey + 40,
-                   bOwner ? ukey.raw_str() : nullptr, digest);
+                   bOwner ? ukey.unsigned_str() : nullptr, digest);
   } else {
     CRYPT_SHA256Start(&sha);
-    CRYPT_SHA256Update(&sha, password.raw_str(), password.GetLength());
+    CRYPT_SHA256Update(&sha, password.unsigned_str(), password.GetLength());
     CRYPT_SHA256Update(&sha, pkey + 40, 8);
     if (bOwner)
-      CRYPT_SHA256Update(&sha, ukey.raw_str(), 48);
+      CRYPT_SHA256Update(&sha, ukey.unsigned_str(), 48);
     CRYPT_SHA256Finish(&sha, digest);
   }
   ByteString ekey = m_pEncryptDict->GetByteStringFor(bOwner ? "OE" : "UE");
@@ -368,7 +368,7 @@
   CRYPT_AESSetKey(&aes, digest, sizeof(digest));
   uint8_t iv[16] = {};
   CRYPT_AESSetIV(&aes, iv);
-  CRYPT_AESDecrypt(&aes, m_EncryptKey.data(), ekey.raw_str(), 32);
+  CRYPT_AESDecrypt(&aes, m_EncryptKey.data(), ekey.unsigned_str(), 32);
   CRYPT_AESSetKey(&aes, m_EncryptKey.data(), m_EncryptKey.size());
   CRYPT_AESSetIV(&aes, iv);
   ByteString perms = m_pEncryptDict->GetByteStringFor("Perms");
@@ -378,7 +378,7 @@
   uint8_t perms_buf[16] = {};
   size_t copy_len =
       std::min(sizeof(perms_buf), static_cast<size_t>(perms.GetLength()));
-  memcpy(perms_buf, perms.raw_str(), copy_len);
+  memcpy(perms_buf, perms.unsigned_str(), copy_len);
   uint8_t buf[16];
   CRYPT_AESDecrypt(&aes, buf, perms_buf, 16);
   if (buf[9] != 'a' || buf[10] != 'd' || buf[11] != 'b')
@@ -467,7 +467,7 @@
   CRYPT_md5_context md5 = CRYPT_MD5Start();
   CRYPT_MD5Update(&md5, kDefaultPasscode);
   if (!m_FileId.IsEmpty())
-    CRYPT_MD5Update(&md5, m_FileId.raw_span());
+    CRYPT_MD5Update(&md5, m_FileId.unsigned_span());
   CRYPT_MD5Finish(&md5, ukeybuf);
   return memcmp(test, ukeybuf, 16) == 0;
 }
@@ -578,7 +578,7 @@
     CRYPT_md5_context md5 = CRYPT_MD5Start();
     CRYPT_MD5Update(&md5, kDefaultPasscode);
     if (!file_id.IsEmpty())
-      CRYPT_MD5Update(&md5, file_id.raw_span());
+      CRYPT_MD5Update(&md5, file_id.unsigned_span());
 
     uint8_t digest[32];
     CRYPT_MD5Finish(&md5, digest);
@@ -614,7 +614,7 @@
     Revision6_Hash(password, digest, nullptr, digest1);
   } else {
     CRYPT_SHA256Start(&sha2);
-    CRYPT_SHA256Update(&sha2, password.raw_str(), password.GetLength());
+    CRYPT_SHA256Update(&sha2, password.unsigned_str(), password.GetLength());
     CRYPT_SHA256Update(&sha2, digest, 8);
     CRYPT_SHA256Finish(&sha2, digest1);
   }
@@ -624,7 +624,7 @@
     Revision6_Hash(password, digest + 8, nullptr, digest1);
   } else {
     CRYPT_SHA256Start(&sha2);
-    CRYPT_SHA256Update(&sha2, password.raw_str(), password.GetLength());
+    CRYPT_SHA256Update(&sha2, password.unsigned_str(), password.GetLength());
     CRYPT_SHA256Update(&sha2, digest + 8, 8);
     CRYPT_SHA256Finish(&sha2, digest1);
   }
diff --git a/core/fpdfapi/parser/cpdf_seekablemultistream_unittest.cpp b/core/fpdfapi/parser/cpdf_seekablemultistream_unittest.cpp
index 040d6e6..95427a5 100644
--- a/core/fpdfapi/parser/cpdf_seekablemultistream_unittest.cpp
+++ b/core/fpdfapi/parser/cpdf_seekablemultistream_unittest.cpp
@@ -45,9 +45,9 @@
   ByteStringView one_view(kOne);
   ByteStringView two_view(kTwo);
   ByteStringView three_view(kThree);
-  auto stream1 = pdfium::MakeRetain<CPDF_Stream>(one_view.raw_span());
-  auto stream2 = pdfium::MakeRetain<CPDF_Stream>(two_view.raw_span());
-  auto stream3 = pdfium::MakeRetain<CPDF_Stream>(three_view.raw_span());
+  auto stream1 = pdfium::MakeRetain<CPDF_Stream>(one_view.unsigned_span());
+  auto stream2 = pdfium::MakeRetain<CPDF_Stream>(two_view.unsigned_span());
+  auto stream3 = pdfium::MakeRetain<CPDF_Stream>(three_view.unsigned_span());
 
   std::vector<RetainPtr<const CPDF_Stream>> streams;
   streams.push_back(std::move(stream1));
diff --git a/core/fpdfapi/parser/cpdf_string.cpp b/core/fpdfapi/parser/cpdf_string.cpp
index 25eedbf..f699eb5 100644
--- a/core/fpdfapi/parser/cpdf_string.cpp
+++ b/core/fpdfapi/parser/cpdf_string.cpp
@@ -57,13 +57,13 @@
 }
 
 WideString CPDF_String::GetUnicodeText() const {
-  return PDF_DecodeText(m_String.raw_span());
+  return PDF_DecodeText(m_String.unsigned_span());
 }
 
 bool CPDF_String::WriteTo(IFX_ArchiveStream* archive,
                           const CPDF_Encryptor* encryptor) const {
   DataVector<uint8_t> encrypted_data;
-  pdfium::span<const uint8_t> data = m_String.raw_span();
+  pdfium::span<const uint8_t> data = m_String.unsigned_span();
   if (encryptor) {
     encrypted_data = encryptor->Encrypt(data);
     data = encrypted_data;
diff --git a/core/fpdfapi/parser/cpdf_syntax_parser.cpp b/core/fpdfapi/parser/cpdf_syntax_parser.cpp
index 7425aa4..52400c1 100644
--- a/core/fpdfapi/parser/cpdf_syntax_parser.cpp
+++ b/core/fpdfapi/parser/cpdf_syntax_parser.cpp
@@ -756,7 +756,7 @@
     // Earlier version of PDF specification doesn't require EOL marker before
     // 'endstream' keyword. If keyword 'endstream' follows the bytes in
     // specified length, it signals the end of stream.
-    if (memcmp(m_WordBuffer.data(), kEndStreamStr.raw_str(),
+    if (memcmp(m_WordBuffer.data(), kEndStreamStr.unterminated_unsigned_str(),
                kEndStreamStr.GetLength()) != 0) {
       substream.Reset();
       len = -1;
@@ -821,7 +821,7 @@
   int numMarkers = ReadEOLMarkers(GetPos());
   if (m_WordSize == static_cast<unsigned int>(kEndObjStr.GetLength()) &&
       numMarkers != 0 &&
-      memcmp(m_WordBuffer.data(), kEndObjStr.raw_str(),
+      memcmp(m_WordBuffer.data(), kEndObjStr.unterminated_unsigned_str(),
              kEndObjStr.GetLength()) == 0) {
     SetPos(end_stream_offset);
   }
diff --git a/core/fpdfapi/parser/fpdf_parser_decode_unittest.cpp b/core/fpdfapi/parser/fpdf_parser_decode_unittest.cpp
index e32b6aa..c724b2b 100644
--- a/core/fpdfapi/parser/fpdf_parser_decode_unittest.cpp
+++ b/core/fpdfapi/parser/fpdf_parser_decode_unittest.cpp
@@ -429,7 +429,7 @@
   for (int pdf_code_point = 0; pdf_code_point < 256; ++pdf_code_point) {
     ByteString original(static_cast<char>(pdf_code_point));
     ByteString reencoded =
-        PDF_EncodeText(PDF_DecodeText(original.raw_span()).AsStringView());
+        PDF_EncodeText(PDF_DecodeText(original.unsigned_span()).AsStringView());
 
     switch (pdf_code_point) {
       case 0x7F:
diff --git a/core/fpdfapi/parser/fpdf_parser_utility.cpp b/core/fpdfapi/parser/fpdf_parser_utility.cpp
index 29d3df0..db94e36 100644
--- a/core/fpdfapi/parser/fpdf_parser_utility.cpp
+++ b/core/fpdfapi/parser/fpdf_parser_utility.cpp
@@ -111,7 +111,7 @@
 }
 
 ByteString PDF_NameEncode(const ByteString& orig) {
-  pdfium::span<const uint8_t> src_span = orig.raw_span();
+  pdfium::span<const uint8_t> src_span = orig.unsigned_span();
   size_t dest_len = 0;
   for (const auto ch : src_span) {
     if (ch >= 0x80 || PDFCharIsWhitespace(ch) || ch == '#' ||
diff --git a/core/fpdfdoc/cpdf_annotlist.cpp b/core/fpdfdoc/cpdf_annotlist.cpp
index ff3ed81..f662e54 100644
--- a/core/fpdfdoc/cpdf_annotlist.cpp
+++ b/core/fpdfdoc/cpdf_annotlist.cpp
@@ -83,7 +83,7 @@
   // /Contents is empty or not. If so, optimize decoding for empty check.
   ByteString contents =
       pParentDict->GetByteStringFor(pdfium::annotation::kContents);
-  if (PDF_DecodeText(contents.raw_span()).IsEmpty()) {
+  if (PDF_DecodeText(contents.unsigned_span()).IsEmpty()) {
     return nullptr;
   }
 
diff --git a/core/fpdfdoc/cpdf_defaultappearance.cpp b/core/fpdfdoc/cpdf_defaultappearance.cpp
index 7536f1e..a0abdad 100644
--- a/core/fpdfdoc/cpdf_defaultappearance.cpp
+++ b/core/fpdfdoc/cpdf_defaultappearance.cpp
@@ -71,7 +71,7 @@
     return std::nullopt;
 
   ByteString csFontNameTag;
-  CPDF_SimpleParser syntax(m_csDA.AsStringView().raw_span());
+  CPDF_SimpleParser syntax(m_csDA.AsStringView().unsigned_span());
   if (FindTagParamFromStart(&syntax, "Tf", 2)) {
     csFontNameTag = ByteString(syntax.GetWord());
     csFontNameTag.Delete(0, 1);
@@ -84,7 +84,7 @@
   if (m_csDA.IsEmpty())
     return std::nullopt;
 
-  CPDF_SimpleParser syntax(m_csDA.AsStringView().raw_span());
+  CPDF_SimpleParser syntax(m_csDA.AsStringView().unsigned_span());
   if (FindTagParamFromStart(&syntax, "g", 1)) {
     float gray = StringToFloat(syntax.GetWord());
     return CFX_Color(CFX_Color::Type::kGray, gray);
diff --git a/core/fpdfdoc/cpdf_formcontrol.cpp b/core/fpdfdoc/cpdf_formcontrol.cpp
index f069178..4d9d653 100644
--- a/core/fpdfdoc/cpdf_formcontrol.cpp
+++ b/core/fpdfdoc/cpdf_formcontrol.cpp
@@ -91,7 +91,7 @@
     csOn = pArray->GetByteStringAt(m_pField->GetControlIndex(this));
   if (csOn.IsEmpty())
     csOn = "Yes";
-  return PDF_DecodeText(csOn.raw_span());
+  return PDF_DecodeText(csOn.unsigned_span());
 }
 
 bool CPDF_FormControl::IsChecked() const {
diff --git a/core/fpdfdoc/cpdf_metadata_unittest.cpp b/core/fpdfdoc/cpdf_metadata_unittest.cpp
index 0618fba..ab71dc2 100644
--- a/core/fpdfdoc/cpdf_metadata_unittest.cpp
+++ b/core/fpdfdoc/cpdf_metadata_unittest.cpp
@@ -16,7 +16,7 @@
       "</node>";
 
   auto stream =
-      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).raw_span());
+      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).unsigned_span());
   CPDF_Metadata metadata(stream);
 
   auto results = metadata.CheckForSharedForm();
@@ -33,7 +33,7 @@
       "</node>";
 
   auto stream =
-      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).raw_span());
+      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).unsigned_span());
   CPDF_Metadata metadata(stream);
 
   auto results = metadata.CheckForSharedForm();
@@ -50,7 +50,7 @@
       "</node>";
 
   auto stream =
-      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).raw_span());
+      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).unsigned_span());
   CPDF_Metadata metadata(stream);
 
   auto results = metadata.CheckForSharedForm();
@@ -67,7 +67,7 @@
       "</node>";
 
   auto stream =
-      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).raw_span());
+      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).unsigned_span());
   CPDF_Metadata metadata(stream);
 
   auto results = metadata.CheckForSharedForm();
@@ -85,7 +85,7 @@
       "</parent></grandparent>";
 
   auto stream =
-      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).raw_span());
+      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).unsigned_span());
   CPDF_Metadata metadata(stream);
 
   auto results = metadata.CheckForSharedForm();
@@ -99,7 +99,7 @@
       "<node></node>";
 
   auto stream =
-      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).raw_span());
+      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).unsigned_span());
   CPDF_Metadata metadata(stream);
 
   auto results = metadata.CheckForSharedForm();
@@ -132,7 +132,7 @@
       "</parent>";
 
   auto stream =
-      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(kData).raw_span());
+      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(kData).unsigned_span());
   CPDF_Metadata metadata(stream);
 
   auto results = metadata.CheckForSharedForm();
@@ -148,7 +148,7 @@
       "</node>";
 
   auto stream =
-      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).raw_span());
+      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).unsigned_span());
   CPDF_Metadata metadata(stream);
 
   auto results = metadata.CheckForSharedForm();
@@ -178,7 +178,7 @@
       "</grandparent>";
 
   auto stream =
-      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).raw_span());
+      pdfium::MakeRetain<CPDF_Stream>(ByteStringView(data).unsigned_span());
   CPDF_Metadata metadata(stream);
 
   auto results = metadata.CheckForSharedForm();
diff --git a/core/fpdfdoc/cpdf_nametree.cpp b/core/fpdfdoc/cpdf_nametree.cpp
index f07aa62..55c8a0d 100644
--- a/core/fpdfdoc/cpdf_nametree.cpp
+++ b/core/fpdfdoc/cpdf_nametree.cpp
@@ -580,5 +580,6 @@
 
 RetainPtr<const CPDF_Array> CPDF_NameTree::LookupNewStyleNamedDest(
     const ByteString& sName) {
-  return GetNamedDestFromObject(LookupValue(PDF_DecodeText(sName.raw_span())));
+  return GetNamedDestFromObject(
+      LookupValue(PDF_DecodeText(sName.unsigned_span())));
 }
diff --git a/core/fxcrt/binary_buffer.cpp b/core/fxcrt/binary_buffer.cpp
index 1fa8bc7..4272cd2 100644
--- a/core/fxcrt/binary_buffer.cpp
+++ b/core/fxcrt/binary_buffer.cpp
@@ -100,7 +100,7 @@
 }
 
 void BinaryBuffer::AppendString(const ByteString& str) {
-  AppendSpan(str.raw_span());
+  AppendSpan(str.unsigned_span());
 }
 
 void BinaryBuffer::AppendUint8(uint8_t value) {
diff --git a/core/fxcrt/bytestring.cpp b/core/fxcrt/bytestring.cpp
index de5ddb5..875968d 100644
--- a/core/fxcrt/bytestring.cpp
+++ b/core/fxcrt/bytestring.cpp
@@ -278,7 +278,7 @@
     return false;
   }
   pdfium::span<const uint8_t> this_span = pdfium::as_bytes(m_pData->span());
-  pdfium::span<const uint8_t> that_span = str.raw_span();
+  pdfium::span<const uint8_t> that_span = str.unsigned_span();
   while (!this_span.empty()) {
     uint8_t this_char = this_span.front();
     uint8_t that_char = that_span.front();
diff --git a/core/fxcrt/bytestring_unittest.cpp b/core/fxcrt/bytestring_unittest.cpp
index 7c2a665..470cd98 100644
--- a/core/fxcrt/bytestring_unittest.cpp
+++ b/core/fxcrt/bytestring_unittest.cpp
@@ -32,7 +32,7 @@
   EXPECT_EQ(3u, abc_span.size());
   EXPECT_EQ(0, memcmp(abc_span.data(), "abc", 3));
 
-  pdfium::span<const uint8_t> abc_raw_span = abc.raw_span();
+  pdfium::span<const uint8_t> abc_raw_span = abc.unsigned_span();
   EXPECT_EQ(3u, abc_raw_span.size());
   EXPECT_EQ(0, memcmp(abc_raw_span.data(), "abc", 3));
 
@@ -1150,7 +1150,7 @@
 
 TEST(ByteStringView, Null) {
   ByteStringView null_string;
-  EXPECT_FALSE(null_string.raw_str());
+  EXPECT_FALSE(null_string.unterminated_unsigned_str());
   EXPECT_EQ(0u, null_string.GetLength());
   EXPECT_TRUE(null_string.IsEmpty());
 
@@ -1158,40 +1158,40 @@
   EXPECT_EQ(null_string, another_null_string);
 
   ByteStringView copied_null_string(null_string);
-  EXPECT_FALSE(copied_null_string.raw_str());
+  EXPECT_FALSE(copied_null_string.unterminated_unsigned_str());
   EXPECT_EQ(0u, copied_null_string.GetLength());
   EXPECT_TRUE(copied_null_string.IsEmpty());
   EXPECT_EQ(null_string, copied_null_string);
 
   ByteStringView span_null_string = pdfium::span<const uint8_t>();
-  EXPECT_FALSE(span_null_string.raw_str());
+  EXPECT_FALSE(span_null_string.unterminated_unsigned_str());
   EXPECT_EQ(0u, span_null_string.GetLength());
   EXPECT_TRUE(span_null_string.IsEmpty());
   EXPECT_EQ(null_string, span_null_string);
 
   ByteStringView empty_string("");  // Pointer to NUL, not NULL pointer.
-  EXPECT_TRUE(empty_string.raw_str());
+  EXPECT_TRUE(empty_string.unterminated_unsigned_str());
   EXPECT_EQ(0u, empty_string.GetLength());
   EXPECT_TRUE(empty_string.IsEmpty());
   EXPECT_EQ(null_string, empty_string);
 
   ByteStringView assigned_null_string("initially not nullptr");
   assigned_null_string = null_string;
-  EXPECT_FALSE(assigned_null_string.raw_str());
+  EXPECT_FALSE(assigned_null_string.unterminated_unsigned_str());
   EXPECT_EQ(0u, assigned_null_string.GetLength());
   EXPECT_TRUE(assigned_null_string.IsEmpty());
   EXPECT_EQ(null_string, assigned_null_string);
 
   ByteStringView assigned_nullptr_string("initially not nullptr");
   assigned_nullptr_string = nullptr;
-  EXPECT_FALSE(assigned_nullptr_string.raw_str());
+  EXPECT_FALSE(assigned_nullptr_string.unterminated_unsigned_str());
   EXPECT_EQ(0u, assigned_nullptr_string.GetLength());
   EXPECT_TRUE(assigned_nullptr_string.IsEmpty());
   EXPECT_EQ(null_string, assigned_nullptr_string);
 
   ByteStringView assigned_span_null_string("initially not null span");
   assigned_span_null_string = pdfium::span<const uint8_t>();
-  EXPECT_FALSE(assigned_span_null_string.raw_str());
+  EXPECT_FALSE(assigned_span_null_string.unterminated_unsigned_str());
   EXPECT_EQ(0u, assigned_span_null_string.GetLength());
   EXPECT_TRUE(assigned_span_null_string.IsEmpty());
   EXPECT_EQ(null_string, assigned_span_null_string);
@@ -1286,7 +1286,7 @@
   cleared_vec.pop_back();
   ByteStringView cleared_string(cleared_vec);
   EXPECT_EQ(0u, cleared_string.GetLength());
-  EXPECT_FALSE(cleared_string.raw_str());
+  EXPECT_FALSE(cleared_string.unterminated_unsigned_str());
 }
 
 TEST(ByteStringView, GetID) {
@@ -1520,7 +1520,7 @@
 
   pdfium::span<const uint8_t> span5(
       pdfium::as_bytes(pdfium::make_span("hello", 5u)));
-  auto raw_span = byte_string_c.raw_span();
+  auto raw_span = byte_string_c.unsigned_span();
   EXPECT_TRUE(
       std::equal(raw_span.begin(), raw_span.end(), span5.begin(), span5.end()));
 }
@@ -1733,14 +1733,14 @@
   EXPECT_TRUE(cstr);
   EXPECT_EQ(0u, strlen(cstr));
 
-  const uint8_t* rstr = empty_str.raw_str();
+  const uint8_t* rstr = empty_str.unsigned_str();
   EXPECT_FALSE(rstr);
 
   pdfium::span<const char> cspan = empty_str.span();
   EXPECT_TRUE(cspan.empty());
   EXPECT_FALSE(cspan.data());
 
-  pdfium::span<const uint8_t> rspan = empty_str.raw_span();
+  pdfium::span<const uint8_t> rspan = empty_str.unsigned_span();
   EXPECT_TRUE(rspan.empty());
   EXPECT_FALSE(rspan.data());
 }
diff --git a/core/fxcrt/cfx_read_only_string_stream.cpp b/core/fxcrt/cfx_read_only_string_stream.cpp
index 5967ed8..74d9344 100644
--- a/core/fxcrt/cfx_read_only_string_stream.cpp
+++ b/core/fxcrt/cfx_read_only_string_stream.cpp
@@ -11,7 +11,8 @@
 
 CFX_ReadOnlyStringStream::CFX_ReadOnlyStringStream(ByteString data)
     : data_(std::move(data)),
-      stream_(pdfium::MakeRetain<CFX_ReadOnlySpanStream>(data_.raw_span())) {}
+      stream_(
+          pdfium::MakeRetain<CFX_ReadOnlySpanStream>(data_.unsigned_span())) {}
 
 CFX_ReadOnlyStringStream::~CFX_ReadOnlyStringStream() = default;
 
diff --git a/core/fxcrt/fx_stream.cpp b/core/fxcrt/fx_stream.cpp
index 63ce068..f63c14b 100644
--- a/core/fxcrt/fx_stream.cpp
+++ b/core/fxcrt/fx_stream.cpp
@@ -45,7 +45,7 @@
 }  // namespace
 
 bool IFX_WriteStream::WriteString(ByteStringView str) {
-  return WriteBlock(str.raw_span());
+  return WriteBlock(str.unsigned_span());
 }
 
 bool IFX_WriteStream::WriteByte(uint8_t byte) {
diff --git a/core/fxcrt/string_template.h b/core/fxcrt/string_template.h
index 9c9ec84..373a5b2 100644
--- a/core/fxcrt/string_template.h
+++ b/core/fxcrt/string_template.h
@@ -33,14 +33,16 @@
 
   // Explicit conversion to UnsignedType*. May return nullptr.
   // Note: Any subsequent modification of |this| will invalidate the result.
-  const UnsignedType* raw_str() const {
+  const UnsignedType* unsigned_str() const {
     return m_pData ? reinterpret_cast<const UnsignedType*>(m_pData->m_String)
                    : nullptr;
   }
 
   // Explicit conversion to StringView.
   // Note: Any subsequent modification of |this| will invalidate the result.
-  StringView AsStringView() const { return StringView(raw_str(), GetLength()); }
+  StringView AsStringView() const {
+    return StringView(unsigned_str(), GetLength());
+  }
 
   // Explicit conversion to span.
   // Note: Any subsequent modification of |this| will invalidate the result.
@@ -51,8 +53,8 @@
 
   // Explicit conversion to spans of unsigned types.
   // Note: Any subsequent modification of |this| will invalidate the result.
-  pdfium::span<const UnsignedType> raw_span() const {
-    return pdfium::make_span(raw_str(), GetLength());
+  pdfium::span<const UnsignedType> unsigned_span() const {
+    return pdfium::make_span(unsigned_str(), GetLength());
   }
 
   // Note: Any subsequent modification of |this| will invalidate iterators.
diff --git a/core/fxcrt/string_view_template.h b/core/fxcrt/string_view_template.h
index 09a529b..341b34a 100644
--- a/core/fxcrt/string_view_template.h
+++ b/core/fxcrt/string_view_template.h
@@ -159,12 +159,14 @@
     return strid << ((4 - size) * 8);
   }
 
-  pdfium::span<const UnsignedType> raw_span() const { return m_Span; }
+  pdfium::span<const UnsignedType> unsigned_span() const { return m_Span; }
   pdfium::span<const CharType> span() const {
     return pdfium::make_span(reinterpret_cast<const CharType*>(m_Span.data()),
                              m_Span.size());
   }
-  const UnsignedType* raw_str() const { return m_Span.data(); }
+  const UnsignedType* unterminated_unsigned_str() const {
+    return m_Span.data();
+  }
   const CharType* unterminated_c_str() const {
     return reinterpret_cast<const CharType*>(m_Span.data());
   }
diff --git a/core/fxcrt/widestring_unittest.cpp b/core/fxcrt/widestring_unittest.cpp
index e913f1e..7803b53 100644
--- a/core/fxcrt/widestring_unittest.cpp
+++ b/core/fxcrt/widestring_unittest.cpp
@@ -1243,8 +1243,9 @@
   };
 
   for (size_t i = 0; i < std::size(utf16be_decode_cases); ++i) {
-    EXPECT_EQ(WideString::FromUTF16BE(utf16be_decode_cases[i].in.raw_span()),
-              utf16be_decode_cases[i].out)
+    EXPECT_EQ(
+        WideString::FromUTF16BE(utf16be_decode_cases[i].in.unsigned_span()),
+        utf16be_decode_cases[i].out)
         << " for case number " << i;
   }
 }
@@ -1262,8 +1263,9 @@
   };
 
   for (size_t i = 0; i < std::size(utf16le_decode_cases); ++i) {
-    EXPECT_EQ(WideString::FromUTF16LE(utf16le_decode_cases[i].in.raw_span()),
-              utf16le_decode_cases[i].out)
+    EXPECT_EQ(
+        WideString::FromUTF16LE(utf16le_decode_cases[i].in.unsigned_span()),
+        utf16le_decode_cases[i].out)
         << " for case number " << i;
   }
 }
@@ -1443,7 +1445,7 @@
   cleared_vec.pop_back();
   WideStringView cleared_string(cleared_vec);
   EXPECT_EQ(0u, cleared_string.GetLength());
-  EXPECT_FALSE(cleared_string.raw_str());
+  EXPECT_FALSE(cleared_string.unterminated_unsigned_str());
 }
 
 TEST(WideStringView, ElementAccess) {
diff --git a/core/fxge/cfx_folderfontinfo.cpp b/core/fxge/cfx_folderfontinfo.cpp
index 30c8f83..6985bb3 100644
--- a/core/fxge/cfx_folderfontinfo.cpp
+++ b/core/fxge/cfx_folderfontinfo.cpp
@@ -250,16 +250,16 @@
 
   static constexpr uint32_t kNameTag =
       CFX_FontMapper::MakeTag('n', 'a', 'm', 'e');
-  ByteString names =
-      LoadTableFromTT(pFile, tables.raw_str(), nTables, kNameTag, filesize);
+  ByteString names = LoadTableFromTT(pFile, tables.unsigned_str(), nTables,
+                                     kNameTag, filesize);
   if (names.IsEmpty())
     return;
 
-  ByteString facename = GetNameFromTT(names.raw_span(), 1);
+  ByteString facename = GetNameFromTT(names.unsigned_span(), 1);
   if (facename.IsEmpty())
     return;
 
-  ByteString style = GetNameFromTT(names.raw_span(), 2);
+  ByteString style = GetNameFromTT(names.unsigned_span(), 2);
   if (style != "Regular")
     facename += " " + style;
 
@@ -271,9 +271,9 @@
   static constexpr uint32_t kOs2Tag =
       CFX_FontMapper::MakeTag('O', 'S', '/', '2');
   ByteString os2 =
-      LoadTableFromTT(pFile, tables.raw_str(), nTables, kOs2Tag, filesize);
+      LoadTableFromTT(pFile, tables.unsigned_str(), nTables, kOs2Tag, filesize);
   if (os2.GetLength() >= 86) {
-    pdfium::span<const uint8_t> p = os2.raw_span().subspan(78);
+    pdfium::span<const uint8_t> p = os2.unsigned_span().subspan(78);
     uint32_t codepages = fxcrt::GetUInt32MSBFirst(p);
     if (codepages & (1U << 17)) {
       m_pMapper->AddInstalledFont(facename, FX_Charset::kShiftJIS);
@@ -390,7 +390,7 @@
     for (size_t i = 0; i < nTables; i++) {
       // TODO(tsepez): iterate over span.
       pdfium::span<const uint8_t> p =
-          pFont->m_FontTables.raw_span().subspan(i * 16);
+          pFont->m_FontTables.unsigned_span().subspan(i * 16);
       if (fxcrt::GetUInt32MSBFirst(p) == table) {
         offset = fxcrt::GetUInt32MSBFirst(p.subspan(8));
         datasize = fxcrt::GetUInt32MSBFirst(p.subspan(12));
diff --git a/core/fxge/fx_font.cpp b/core/fxge/fx_font.cpp
index ddde3db..5c9d1b4 100644
--- a/core/fxge/fx_font.cpp
+++ b/core/fxge/fx_font.cpp
@@ -119,7 +119,7 @@
           return ByteString();
         }
 
-        return WideString::FromUTF16BE(utf16_be.raw_span()).ToUTF8();
+        return WideString::FromUTF16BE(utf16_be.unsigned_span()).ToUTF8();
       }
     }
   }
diff --git a/fpdfsdk/cpdfsdk_appstream.cpp b/fpdfsdk/cpdfsdk_appstream.cpp
index 6ee6d39..28a919c 100644
--- a/fpdfsdk/cpdfsdk_appstream.cpp
+++ b/fpdfsdk/cpdfsdk_appstream.cpp
@@ -1852,7 +1852,7 @@
   RetainPtr<CPDF_Dictionary> stream_dict = stream->GetMutableDict();
   stream_dict->SetMatrixFor("Matrix", widget_->GetMatrix());
   stream_dict->SetRectFor("BBox", widget_->GetRotatedRect());
-  stream->SetDataAndRemoveFilter(sContents.raw_span());
+  stream->SetDataAndRemoveFilter(sContents.unsigned_span());
 }
 
 void CPDFSDK_AppStream::Remove(ByteStringView sAPType) {
diff --git a/fpdfsdk/cpdfsdk_interactiveform.cpp b/fpdfsdk/cpdfsdk_interactiveform.cpp
index fbf09a0..f469ce9 100644
--- a/fpdfsdk/cpdfsdk_interactiveform.cpp
+++ b/fpdfsdk/cpdfsdk_interactiveform.cpp
@@ -73,7 +73,7 @@
 
 ByteString FDFToURLEncodedData(ByteString buffer) {
   std::unique_ptr<CFDF_Document> pFDF =
-      CFDF_Document::ParseMemory(buffer.raw_span());
+      CFDF_Document::ParseMemory(buffer.unsigned_span());
   if (!pFDF)
     return buffer;
 
@@ -94,7 +94,7 @@
     WideString name = pField->GetUnicodeTextFor("T");
     ByteString name_b = name.ToDefANSI();
     ByteString csBValue = pField->GetByteStringFor("V");
-    WideString csWValue = PDF_DecodeText(csBValue.raw_span());
+    WideString csWValue = PDF_DecodeText(csBValue.unsigned_span());
     ByteString csValue_b = csWValue.ToDefANSI();
     encoded_data << name_b << "=" << csValue_b;
     if (i != pFields->size() - 1)
@@ -452,7 +452,7 @@
       return false;
   }
 
-  m_pFormFillEnv->SubmitForm(text_buf.raw_span(), csDestination);
+  m_pFormFillEnv->SubmitForm(text_buf.unsigned_span(), csDestination);
   return true;
 }
 
@@ -478,7 +478,7 @@
   if (fdf_buffer.IsEmpty())
     return false;
 
-  m_pFormFillEnv->SubmitForm(fdf_buffer.raw_span(), sDestination);
+  m_pFormFillEnv->SubmitForm(fdf_buffer.unsigned_span(), sDestination);
   return true;
 }
 
diff --git a/fpdfsdk/fpdf_annot.cpp b/fpdfsdk/fpdf_annot.cpp
index f2cd947..8a940b3 100644
--- a/fpdfsdk/fpdf_annot.cpp
+++ b/fpdfsdk/fpdf_annot.cpp
@@ -1112,7 +1112,7 @@
   auto new_stream = pDoc->NewIndirect<CPDF_Stream>(std::move(stream_dict));
   ByteString new_stream_data =
       PDF_EncodeText(WideStringFromFPDFWideString(value).AsStringView());
-  new_stream->SetData(new_stream_data.raw_span());
+  new_stream->SetData(new_stream_data.unsigned_span());
 
   // Storing reference to indirect object in annotation's AP
   if (!pApDict) {
diff --git a/fpdfsdk/fpdf_attachment.cpp b/fpdfsdk/fpdf_attachment.cpp
index b19f9f0..8fc5e54 100644
--- a/fpdfsdk/fpdf_attachment.cpp
+++ b/fpdfsdk/fpdf_attachment.cpp
@@ -36,7 +36,7 @@
 ByteString CFXByteStringHexDecode(const ByteString& bsHex) {
   std::unique_ptr<uint8_t, FxFreeDeleter> result;
   uint32_t size = 0;
-  HexDecode(bsHex.raw_span(), &result, &size);
+  HexDecode(bsHex.unsigned_span(), &result, &size);
   return ByteString(result.get(), size);
 }
 
diff --git a/fpdfsdk/fpdf_edittext.cpp b/fpdfsdk/fpdf_edittext.cpp
index a439897..25c3b04 100644
--- a/fpdfsdk/fpdf_edittext.cpp
+++ b/fpdfsdk/fpdf_edittext.cpp
@@ -542,8 +542,8 @@
 
   CreateDescendantFontsArray(doc, font_dict, cid_font_dict->GetObjNum());
 
-  auto to_unicode_stream =
-      doc->NewIndirect<CPDF_Stream>(ByteStringView(to_unicode_cmap).raw_span());
+  auto to_unicode_stream = doc->NewIndirect<CPDF_Stream>(
+      ByteStringView(to_unicode_cmap).unsigned_span());
   font_dict->SetNewFor<CPDF_Reference>("ToUnicode", doc,
                                        to_unicode_stream->GetObjNum());
   return CPDF_DocPageData::FromDocument(doc)->GetFont(font_dict);
diff --git a/fpdfsdk/fpdf_flatten.cpp b/fpdfsdk/fpdf_flatten.cpp
index 3ba9ca6..b5da321 100644
--- a/fpdfsdk/fpdf_flatten.cpp
+++ b/fpdfsdk/fpdf_flatten.cpp
@@ -182,7 +182,7 @@
     const ByteString& contents) {
   auto pNewContents =
       pDocument->NewIndirect<CPDF_Stream>(pDocument->New<CPDF_Dictionary>());
-  pNewContents->SetData(contents.raw_span());
+  pNewContents->SetData(contents.unsigned_span());
   return pNewContents->MakeReference(pDocument);
 }
 
@@ -215,7 +215,7 @@
       sStream += ByteString(pAcc->GetSpan());
       sStream += "\nQ";
     }
-    pContentsStream->SetDataAndRemoveFilter(sStream.raw_span());
+    pContentsStream->SetDataAndRemoveFilter(sStream.unsigned_span());
     pContentsArray = pDocument->NewIndirect<CPDF_Array>();
     pContentsArray->AppendNew<CPDF_Reference>(pDocument,
                                               pContentsStream->GetObjNum());
@@ -413,7 +413,7 @@
     ByteString str(buf);
     sStream += ByteString::Format("q %s cm /%s Do Q\n", str.c_str(),
                                   sFormName.c_str());
-    pNewXObject->SetDataAndRemoveFilter(sStream.raw_span());
+    pNewXObject->SetDataAndRemoveFilter(sStream.unsigned_span());
   }
   pPageDict->RemoveFor("Annots");
   return FLATTEN_SUCCESS;
diff --git a/fpdfsdk/fpdf_ppo.cpp b/fpdfsdk/fpdf_ppo.cpp
index 6710b09..a8a42a0 100644
--- a/fpdfsdk/fpdf_ppo.cpp
+++ b/fpdfsdk/fpdf_ppo.cpp
@@ -640,7 +640,7 @@
       pAcc->LoadAllDataFiltered();
       bsSrcContentStream = ByteString(pAcc->GetSpan());
     }
-    pNewXObject->SetDataAndRemoveFilter(bsSrcContentStream.raw_span());
+    pNewXObject->SetDataAndRemoveFilter(bsSrcContentStream.unsigned_span());
   }
   return pNewXObject;
 }
@@ -681,7 +681,7 @@
 
   auto pStream =
       dest()->NewIndirect<CPDF_Stream>(dest()->New<CPDF_Dictionary>());
-  pStream->SetData(bsContent.raw_span());
+  pStream->SetData(bsContent.unsigned_span());
   pDestPageDict->SetNewFor<CPDF_Reference>(pdfium::page_object::kContents,
                                            dest(), pStream->GetObjNum());
 }
diff --git a/fpdfsdk/fpdf_transformpage.cpp b/fpdfsdk/fpdf_transformpage.cpp
index c8cbcaf..de1ffe5 100644
--- a/fpdfsdk/fpdf_transformpage.cpp
+++ b/fpdfsdk/fpdf_transformpage.cpp
@@ -233,7 +233,7 @@
 
   auto pEndStream =
       pDoc->NewIndirect<CPDF_Stream>(pDoc->New<CPDF_Dictionary>());
-  pEndStream->SetData(ByteStringView(" Q").raw_span());
+  pEndStream->SetData(ByteStringView(" Q").unsigned_span());
 
   RetainPtr<CPDF_Array> pContentArray = ToArray(pContentObj);
   if (pContentArray) {
diff --git a/fpdfsdk/fpdf_view.cpp b/fpdfsdk/fpdf_view.cpp
index 6b0a1c1..2e88578 100644
--- a/fpdfsdk/fpdf_view.cpp
+++ b/fpdfsdk/fpdf_view.cpp
@@ -1252,7 +1252,7 @@
         break;
       i++;
     }
-    wsName = PDF_DecodeText(bsName.raw_span());
+    wsName = PDF_DecodeText(bsName.unsigned_span());
   } else {
     pDestObj = name_tree->LookupValueAndName(index, &wsName);
   }
diff --git a/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp b/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp
index 38232c7..199e0a3 100644
--- a/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp
+++ b/fpdfsdk/fpdfxfa/cpdfxfa_docenvironment.cpp
@@ -503,7 +503,7 @@
         continue;
       }
       if (i == pArray->size() - 1) {
-        WideString wPath = WideString::FromUTF16LE(bs.raw_span());
+        WideString wPath = WideString::FromUTF16LE(bs.unsigned_span());
         ByteString bPath = wPath.ToUTF8();
         static const char kFormat[] =
             "\n<pdf href=\"%s\" xmlns=\"http://ns.adobe.com/xdp/pdf/\"/>";
diff --git a/fxbarcode/pdf417/BC_PDF417HighLevelEncoder.cpp b/fxbarcode/pdf417/BC_PDF417HighLevelEncoder.cpp
index d903b8f..f052484 100644
--- a/fxbarcode/pdf417/BC_PDF417HighLevelEncoder.cpp
+++ b/fxbarcode/pdf417/BC_PDF417HighLevelEncoder.cpp
@@ -116,7 +116,7 @@
         p += t;
       } else {
         std::optional<size_t> b =
-            DetermineConsecutiveBinaryCount(result, bytes.raw_span(), p);
+            DetermineConsecutiveBinaryCount(result, bytes.unsigned_span(), p);
         if (!b.has_value())
           return std::nullopt;
 
@@ -124,9 +124,9 @@
         if (b_value == 0)
           b_value = 1;
         if (b_value == 1 && encodingMode == EncodingMode::kText) {
-          EncodeBinary(bytes.raw_span(), p, 1, EncodingMode::kText, &sb);
+          EncodeBinary(bytes.unsigned_span(), p, 1, EncodingMode::kText, &sb);
         } else {
-          EncodeBinary(bytes.raw_span(), p, b_value, encodingMode, &sb);
+          EncodeBinary(bytes.unsigned_span(), p, b_value, encodingMode, &sb);
           encodingMode = EncodingMode::kByte;
           textSubMode = SubMode::kAlpha;
         }
diff --git a/fxjs/cjs_document.cpp b/fxjs/cjs_document.cpp
index 41046c6..e37cf01 100644
--- a/fxjs/cjs_document.cpp
+++ b/fxjs/cjs_document.cpp
@@ -394,8 +394,8 @@
     cMsg = pRuntime->ToWideString(newParams[5]);
 
   pRuntime->BeginBlock();
-  m_pFormFillEnv->JS_docmailForm(sTextBuf.raw_span(), bUI, cTo, cSubject, cCc,
-                                 cBcc, cMsg);
+  m_pFormFillEnv->JS_docmailForm(sTextBuf.unsigned_span(), bUI, cTo, cSubject,
+                                 cCc, cBcc, cMsg);
   pRuntime->EndBlock();
   return CJS_Result::Success();
 }
diff --git a/xfa/fxfa/parser/cxfa_node.cpp b/xfa/fxfa/parser/cxfa_node.cpp
index af7eeba..51a269e 100644
--- a/xfa/fxfa/parser/cxfa_node.cpp
+++ b/xfa/fxfa/parser/cxfa_node.cpp
@@ -407,7 +407,8 @@
   if (bsStr.IsEmpty())
     return result;
 
-  DataVector<uint8_t> buffer = XFA_RemoveBase64Whitespace(bsStr.raw_span());
+  DataVector<uint8_t> buffer =
+      XFA_RemoveBase64Whitespace(bsStr.unsigned_span());
   result.reserve(3 * (buffer.size() / 4));
 
   uint32_t dwLimb = 0;