diff --git a/browser/installer/windows/nsis/uninstaller.nsi b/browser/installer/windows/nsis/uninstaller.nsi
old mode 100755
new mode 100644
index becbb0f70c84eb7f2d9bff5a3aedcbb7a78a61cf..05835d2088ab631316a25a9f0728898bd7998d8d
--- a/browser/installer/windows/nsis/uninstaller.nsi
+++ b/browser/installer/windows/nsis/uninstaller.nsi
@@ -516,6 +516,7 @@ Section "Uninstall"
   ${un.RegCleanFileHandler}  ".svg"   "FirefoxHTML-$AppUserModelID"
   ${un.RegCleanFileHandler}  ".webp"  "FirefoxHTML-$AppUserModelID"
   ${un.RegCleanFileHandler}  ".avif"  "FirefoxHTML-$AppUserModelID"
+  ${un.RegCleanFileHandler}  ".jxl"  "FirefoxHTML-$AppUserModelID"
 
   ${un.RegCleanFileHandler}  ".pdf"   "FirefoxPDF-$AppUserModelID"
 
