diff --git a/src/LineBreak.ts b/src/LineBreak.ts
index f92ff24..faa1765 100644
--- a/src/LineBreak.ts
+++ b/src/LineBreak.ts
@@ -269,6 +269,11 @@ const _lineBreakAtIndex = (
         return BREAK_NOT_ALLOWED;
     }
 
+    // see LB9 in codePointsToCharacterClasses
+    if (indicies[index] === indicies[index -1]) {
+       return BREAK_NOT_ALLOWED;
+    }
+
     let currentIndex = index - 1;
     if (Array.isArray(forbiddenBreaks) && forbiddenBreaks[currentIndex] === true) {
         return BREAK_NOT_ALLOWED;
@@ -311,11 +316,6 @@ const _lineBreakAtIndex = (
         return BREAK_NOT_ALLOWED;
     }
 
-    // zwj emojis
-    if ((current === EB || current === EM) && UnicodeTrie.get(codePoints[afterIndex]) === ZWJ) {
-        return BREAK_NOT_ALLOWED;
-    }
-
     // LB11 Do not break before or after Word joiner and related characters.
     if (current === WJ || next === WJ) {
         return BREAK_NOT_ALLOWED;
diff --git a/tests/LineBreaker.ts b/tests/LineBreaker.ts
index 7f0ec21..47e2319 100644
--- a/tests/LineBreaker.ts
+++ b/tests/LineBreaker.ts
@@ -18,7 +18,7 @@ describe('LineBreaker', () => {
     });
 
     it('should handle zwj emojis', () => {
-        const breaker = LineBreaker('Text with zwj emojis 👨‍👩‍👧‍👦 and modifiers 🤷🏾‍♂️.');
+        const breaker = LineBreaker('Text with zwj emojis 👨‍👩‍👧‍👦 and 🏳️‍🌈 and modifiers 🤷🏾‍♂️.');
 
         const words = [];
         let bk;
@@ -29,7 +29,7 @@ describe('LineBreaker', () => {
             }
         }
 
-        deepEqual(words, ['Text ', 'with ', 'zwj ', 'emojis ', '👨‍👩‍👧‍👦 ', 'and ', 'modifiers ', '🤷🏾‍♂️.']);
+        deepEqual(words, ['Text ', 'with ', 'zwj ', 'emojis ', '👨‍👩‍👧‍👦 ', 'and ', '🏳️‍🌈 ', 'and ', 'modifiers ', '🤷🏾‍♂️.']);
     });
 
     it('Works with options', () => {