diff --git a/engine/src/flutter/include/minikin/WordBreaker.h b/engine/src/flutter/include/minikin/WordBreaker.h
index 8c0050236e..c4aa1514a0 100644
--- a/engine/src/flutter/include/minikin/WordBreaker.h
+++ b/engine/src/flutter/include/minikin/WordBreaker.h
@@ -63,7 +63,7 @@ private:
 
     // state for the email address / url detector
     ssize_t mScanOffset;
-    bool mSuppressHyphen;
+    bool mInEmailOrUrl;
 };
 
 }  // namespace
diff --git a/engine/src/flutter/libs/minikin/WordBreaker.cpp b/engine/src/flutter/libs/minikin/WordBreaker.cpp
index f438cd5546..edac993d44 100644
--- a/engine/src/flutter/libs/minikin/WordBreaker.cpp
+++ b/engine/src/flutter/libs/minikin/WordBreaker.cpp
@@ -43,7 +43,7 @@ void WordBreaker::setText(const uint16_t* data, size_t size) {
     mLast = 0;
     mCurrent = 0;
     mScanOffset = 0;
-    mSuppressHyphen = false;
+    mInEmailOrUrl = false;
     UErrorCode status = U_ZERO_ERROR;
     utext_openUChars(&mUText, data, size, &status);
     mBreakIterator->setText(&mUText, status);
@@ -62,6 +62,17 @@ enum ScanState {
     SAW_COLON_SLASH_SLASH,
 };
 
+// Chicago Manual of Style recommends breaking after these characters in URLs and email addresses
+static bool breakAfter(uint16_t c) {
+    return c == ':' || c == '=' || c == '&';
+}
+
+// Chicago Manual of Style recommends breaking before these characters in URLs and email addresses
+static bool breakBefore(uint16_t c) {
+    return c == '~' || c == '.' || c == ',' || c == '-' || c == '_' || c == '?' || c == '#'
+            || c == '%' || c == '=' || c == '&';
+}
+
 ssize_t WordBreaker::next() {
     mLast = mCurrent;
 
@@ -88,23 +99,45 @@ ssize_t WordBreaker::next() {
             }
         }
         if (state == SAW_AT || state == SAW_COLON_SLASH_SLASH) {
-            // no line breaks in entire email address or url
-            // TODO: refine this according to Chicago Manual of Style rules
-            while (i < mTextSize && mText[i] == ' ') {
-                i++;
+            if (!mBreakIterator->isBoundary(i)) {
+                i = mBreakIterator->following(i);
             }
-            mCurrent = i;
-            mSuppressHyphen = true;
-            // Setting mIteratorWasReset will cause next break to be computed following
-            // mCurrent, rather than following the current ICU iterator location.
+            mInEmailOrUrl = true;
             mIteratorWasReset = true;
-            if (mBreakIterator->isBoundary(mCurrent)) {
-                return mCurrent;
-            }
         } else {
-            mScanOffset = i;
-            mSuppressHyphen = false;
+            mInEmailOrUrl = false;
         }
+        mScanOffset = i;
+    }
+
+    if (mInEmailOrUrl) {
+        // special rules for email addresses and URL's as per Chicago Manual of Style (16th ed.)
+        uint16_t lastChar = mText[mLast];
+        ssize_t i;
+        for (i = mLast + 1; i < mScanOffset; i++) {
+            if (breakAfter(lastChar)) {
+                break;
+            }
+            // break after double slash
+            if (lastChar == '/' && i >= mLast + 2 && mText[i - 2] == '/') {
+                break;
+            }
+            uint16_t thisChar = mText[i];
+            // never break after hyphen
+            if (lastChar != '-') {
+                if (breakBefore(thisChar)) {
+                    break;
+                }
+                // break before single slash
+                if (thisChar == '/' && lastChar != '/' &&
+                            !(i + 1 < mScanOffset && mText[i + 1] == '/')) {
+                    break;
+                }
+            }
+            lastChar = thisChar;
+        }
+        mCurrent = i;
+        return mCurrent;
     }
 
     int32_t result;
@@ -122,7 +155,7 @@ ssize_t WordBreaker::next() {
 }
 
 ssize_t WordBreaker::wordStart() const {
-    if (mSuppressHyphen) {
+    if (mInEmailOrUrl) {
         return mLast;
     }
     ssize_t result = mLast;
@@ -142,7 +175,7 @@ ssize_t WordBreaker::wordStart() const {
 }
 
 ssize_t WordBreaker::wordEnd() const {
-    if (mSuppressHyphen) {
+    if (mInEmailOrUrl) {
         return mLast;
     }
     ssize_t result = mCurrent;
diff --git a/engine/src/flutter/tests/WordBreakerTests.cpp b/engine/src/flutter/tests/WordBreakerTests.cpp
index 4111a1b1f4..284b02cb28 100644
--- a/engine/src/flutter/tests/WordBreakerTests.cpp
+++ b/engine/src/flutter/tests/WordBreakerTests.cpp
@@ -85,7 +85,9 @@ TEST_F(WordBreakerTest, email) {
     breaker.setLocale(icu::Locale::getEnglish());
     breaker.setText(buf, NELEM(buf));
     EXPECT_EQ(0, breaker.current());
-    EXPECT_EQ(16, breaker.next());  // after "foo@example.com "
+    EXPECT_EQ(11, breaker.next());  // after "foo@example"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(16, breaker.next());  // after ".com "
     EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
     EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
     EXPECT_EQ(16, breaker.wordStart());  // "x"
@@ -99,13 +101,19 @@ TEST_F(WordBreakerTest, mailto) {
     breaker.setLocale(icu::Locale::getEnglish());
     breaker.setText(buf, NELEM(buf));
     EXPECT_EQ(0, breaker.current());
-    EXPECT_EQ(23, breaker.next());  // after "mailto:foo@example.com "
+    EXPECT_EQ(7, breaker.next());  // after "mailto:"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(18, breaker.next());  // after "foo@example"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(23, breaker.next());  // after ".com "
     EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
     EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
     EXPECT_EQ(23, breaker.wordStart());  // "x"
     EXPECT_EQ(24, breaker.wordEnd());
 }
 
+// The current logic always places a line break after a detected email address or URL
+// and an immediately following non-ASCII character.
 TEST_F(WordBreakerTest, emailNonAscii) {
     uint16_t buf[] = {'f', 'o', 'o', '@', 'e', 'x', 'a', 'm', 'p', 'l', 'e', '.', 'c', 'o', 'm',
         0x4E00};
@@ -113,7 +121,9 @@ TEST_F(WordBreakerTest, emailNonAscii) {
     breaker.setLocale(icu::Locale::getEnglish());
     breaker.setText(buf, NELEM(buf));
     EXPECT_EQ(0, breaker.current());
-    EXPECT_EQ(15, breaker.next());  // after "foo@example.com"
+    EXPECT_EQ(11, breaker.next());  // after "foo@example"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(15, breaker.next());  // after ".com"
     EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
     EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
     EXPECT_EQ(15, breaker.wordStart());  // "一"
@@ -127,13 +137,31 @@ TEST_F(WordBreakerTest, emailCombining) {
     breaker.setLocale(icu::Locale::getEnglish());
     breaker.setText(buf, NELEM(buf));
     EXPECT_EQ(0, breaker.current());
-    EXPECT_EQ(17, breaker.next());  // after "foo@example.com̃"
+    EXPECT_EQ(11, breaker.next());  // after "foo@example"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(17, breaker.next());  // after ".com̃ "
     EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
     EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
     EXPECT_EQ(17, breaker.wordStart());  // "x"
     EXPECT_EQ(18, breaker.wordEnd());
 }
 
+TEST_F(WordBreakerTest, lonelyAt) {
+    uint16_t buf[] = {'a', ' ', '@', ' ', 'b'};
+    WordBreaker breaker;
+    breaker.setLocale(icu::Locale::getEnglish());
+    breaker.setText(buf, NELEM(buf));
+    EXPECT_EQ(0, breaker.current());
+    EXPECT_EQ(2, breaker.next());  // after "a "
+    EXPECT_EQ(0, breaker.wordStart());  // "a"
+    EXPECT_EQ(1, breaker.wordEnd());
+    EXPECT_EQ(4, breaker.next());  // after "@ "
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
+    EXPECT_EQ(4, breaker.wordStart());  // "b"
+    EXPECT_EQ(5, breaker.wordEnd());
+}
+
 TEST_F(WordBreakerTest, url) {
     uint16_t buf[] = {'h', 't', 't', 'p', ':', '/', '/', 'e', 'x', 'a', 'm', 'p', 'l', 'e',
         '.', 'c', 'o', 'm', ' ', 'x'};
@@ -141,9 +169,101 @@ TEST_F(WordBreakerTest, url) {
     breaker.setLocale(icu::Locale::getEnglish());
     breaker.setText(buf, NELEM(buf));
     EXPECT_EQ(0, breaker.current());
-    EXPECT_EQ(19, breaker.next());  // after "http://example.com "
+    EXPECT_EQ(5, breaker.next());  // after "http:"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(7, breaker.next());  // after "//"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(14, breaker.next());  // after "example"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(19, breaker.next());  // after ".com "
     EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
     EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
     EXPECT_EQ(19, breaker.wordStart());  // "x"
     EXPECT_EQ(20, breaker.wordEnd());
 }
+
+// Breaks according to section 14.12 of Chicago Manual of Style, *URLs or DOIs and line breaks*
+TEST_F(WordBreakerTest, urlBreakChars) {
+    uint16_t buf[] = {'h', 't', 't', 'p', ':', '/', '/', 'a', '.', 'b', '/', '~', 'c', ',', 'd',
+        '-', 'e', '?', 'f', '=', 'g', '&', 'h', '#', 'i', '%', 'j', '_', 'k', '/', 'l'};
+    WordBreaker breaker;
+    breaker.setLocale(icu::Locale::getEnglish());
+    breaker.setText(buf, NELEM(buf));
+    EXPECT_EQ(0, breaker.current());
+    EXPECT_EQ(5, breaker.next());  // after "http:"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(7, breaker.next());  // after "//"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(8, breaker.next());  // after "a"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(10, breaker.next());  // after ".b"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(11, breaker.next());  // after "/"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(13, breaker.next());  // after "~c"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(15, breaker.next());  // after ",d"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(17, breaker.next());  // after "-e"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(19, breaker.next());  // after "?f"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(20, breaker.next());  // after "="
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(21, breaker.next());  // after "g"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(22, breaker.next());  // after "&"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(23, breaker.next());  // after "h"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(25, breaker.next());  // after "#i"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(27, breaker.next());  // after "%j"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(29, breaker.next());  // after "_k"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+}
+
+TEST_F(WordBreakerTest, urlNoHyphenBreak) {
+    uint16_t buf[] = {'h', 't', 't', 'p', ':', '/', '/', 'a', '-', '/', 'b'};
+    WordBreaker breaker;
+    breaker.setLocale(icu::Locale::getEnglish());
+    breaker.setText(buf, NELEM(buf));
+    EXPECT_EQ(0, breaker.current());
+    EXPECT_EQ(5, breaker.next());  // after "http:"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(7, breaker.next());  // after "//"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(8, breaker.next());  // after "a"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+}
+
+TEST_F(WordBreakerTest, urlEndsWithSlash) {
+    uint16_t buf[] = {'h', 't', 't', 'p', ':', '/', '/', 'a', '/'};
+    WordBreaker breaker;
+    breaker.setLocale(icu::Locale::getEnglish());
+    breaker.setText(buf, NELEM(buf));
+    EXPECT_EQ(0, breaker.current());
+    EXPECT_EQ(5, breaker.next());  // after "http:"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(7, breaker.next());  // after "//"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ(8, breaker.next());  // after "a"
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+    EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+}
+
+TEST_F(WordBreakerTest, emailStartsWithSlash) {
+    uint16_t buf[] = {'/', 'a', '@', 'b'};
+    WordBreaker breaker;
+    breaker.setLocale(icu::Locale::getEnglish());
+    breaker.setText(buf, NELEM(buf));
+    EXPECT_EQ(0, breaker.current());
+    EXPECT_EQ((ssize_t)NELEM(buf), breaker.next());  // end
+    EXPECT_TRUE(breaker.wordStart() >= breaker.wordEnd());
+}