diff --git a/web/src/engine/predictive-text/worker-thread/src/main/correction/context-tokenization.ts b/web/src/engine/predictive-text/worker-thread/src/main/correction/context-tokenization.ts
index 706b6d246a..2db1782fa8 100644
--- a/web/src/engine/predictive-text/worker-thread/src/main/correction/context-tokenization.ts
+++ b/web/src/engine/predictive-text/worker-thread/src/main/correction/context-tokenization.ts
@@ -706,19 +706,23 @@ export function traceInsertEdits(tokens: string[], transform: Transform): {
   firstInsertPostIndex: number
 } {
   let insert = transform.insert;
+  let insertLen = KMWString.length(insert);
   const stackedInserts: string[] = [];
   let firstInsertPostIndex: number;
 
   if(insert.length > 0) {
     for(let index = tokens.length - 1; index >= 0; index--) {
+      const tokenLen = KMWString.length(tokens[index]);
+
       const currentToken = tokens[index];
-      if(KMWString.length(currentToken) >= KMWString.length(insert)) {
+      if(tokenLen >= insertLen) {
         stackedInserts.push(insert);
         firstInsertPostIndex = index;
         break;
       }
 
-      insert = insert.substring(0, insert.length - currentToken.length);
+      insert = KMWString.substring(insert, 0, insertLen - tokenLen);
+      insertLen -= tokenLen;
       stackedInserts.push(currentToken);
       firstInsertPostIndex = index;
     }