mozilla/pdf.js

web/pdf_viewer.js

@@ -71,6 +71,13 @@ class PdfViewer {
         url,
         rangeChunkSize: 65536,
         disableAutoFetch: false,
+        // PDF.js >= 5 decodes CCITT-G4/JBIG2 (B/W scans), JPEG2000 and ICC
+        // color via WASM modules fetched from wasmUrl. Without these URLs
+        // the decoders fail silently (ignoreErrors default) and scanned
+        // pages render as blank white canvases of the correct size.
+        wasmUrl: "/pdfjs/wasm/",
+        standardFontDataUrl: "/pdfjs/standard_fonts/",
+        iccUrl: "/pdfjs/iccs/",
       });
       this.loadingTask = task;
 
@@ -259,4 +266,4 @@ function errorMsg(err) {
   return err instanceof Error ? err.message : String(err);
 }
 
-globalThis.PdfViewer = PdfViewer;
+globalThis.PdfViewer = PdfViewer;