diff --git a/test/pdfs/.gitignore b/test/pdfs/.gitignore
index 119701c04..d8859cf1d 100644
--- a/test/pdfs/.gitignore
+++ b/test/pdfs/.gitignore
@@ -538,3 +538,4 @@
 !bug1782186.pdf
 !tracemonkey_a11y.pdf
 !bug1782564.pdf
+!issue15340.pdf
diff --git a/test/pdfs/issue15340.pdf b/test/pdfs/issue15340.pdf
new file mode 100644
index 000000000..439f1602f
Binary files /dev/null and b/test/pdfs/issue15340.pdf differ
diff --git a/test/unit/pdf_find_controller_spec.js b/test/unit/pdf_find_controller_spec.js
index 86e6281ac..f50ee7840 100644
--- a/test/unit/pdf_find_controller_spec.js
+++ b/test/unit/pdf_find_controller_spec.js
@@ -626,4 +626,25 @@ describe("pdf_find_controller", function () {
       pageMatchesLength: [[8]],
     });
   });
+
+  it("performs a search in a text containing an ideographic at the end of a line", async function () {
+    const { eventBus, pdfFindController } = await initPdfFindController(
+      "issue15340.pdf"
+    );
+
+    await testSearch({
+      eventBus,
+      pdfFindController,
+      state: {
+        query: "検知機構",
+      },
+      matchesPerPage: [1],
+      selectedMatch: {
+        pageIndex: 0,
+        matchIndex: 0,
+      },
+      pageMatches: [[29]],
+      pageMatchesLength: [[4]],
+    });
+  });
 });
diff --git a/web/pdf_find_controller.js b/web/pdf_find_controller.js
index cfadec222..a0218035b 100644
--- a/web/pdf_find_controller.js
+++ b/web/pdf_find_controller.js
@@ -126,7 +126,7 @@ function normalize(text) {
   } else {
     // Compile the regular expression for text normalization once.
     const replace = Object.keys(CHARACTERS_TO_NORMALIZE).join("");
-    const regexp = `([${replace}])|(\\p{M}+(?:-\\n)?)|(\\S-\\n)|(\\n)`;
+    const regexp = `([${replace}])|(\\p{M}+(?:-\\n)?)|(\\S-\\n)|(\\p{Ideographic}\\n)|(\\n)`;
 
     if (syllablePositions.length === 0) {
       // Most of the syllables belong to Hangul so there are no need
@@ -188,7 +188,7 @@ function normalize(text) {
 
   normalized = normalized.replace(
     normalizationRegex,
-    (match, p1, p2, p3, p4, p5, i) => {
+    (match, p1, p2, p3, p4, p5, p6, i) => {
       i -= shiftOrigin;
       if (p1) {
         // Maybe fractions or quotations mark...
@@ -248,6 +248,15 @@ function normalize(text) {
       }
 
       if (p4) {
+        // An ideographic at the end of a line doesn't imply adding an extra
+        // white space.
+        positions.push([i - shift + 1, shift]);
+        shiftOrigin += 1;
+        eol += 1;
+        return p4.charAt(0);
+      }
+
+      if (p5) {
         // eol is replaced by space: "foo\nbar" is likely equivalent to
         // "foo bar".
         positions.push([i - shift + 1, shift - 1]);
@@ -257,7 +266,7 @@ function normalize(text) {
         return " ";
       }
 
-      // p5
+      // p6
       if (i + eol === syllablePositions[syllableIndex]?.[1]) {
         // A syllable (1 char) is replaced with several chars (n) so
         // newCharsLen = n - 1.
@@ -269,7 +278,7 @@ function normalize(text) {
         shift -= newCharLen;
         shiftOrigin += newCharLen;
       }
-      return p5;
+      return p6;
     }
   );