diff --git a/browser/installer/windows/nsis/uninstaller.nsi b/browser/installer/windows/nsis/uninstaller.nsi
old mode 100755
new mode 100644
index a193a94e4893a8b07111d83ebdd2a6488a98be7a..ab7d84abbf6d9442cbc299194c4ffb74c5785723
--- a/browser/installer/windows/nsis/uninstaller.nsi
+++ b/browser/installer/windows/nsis/uninstaller.nsi
@@ -515,6 +515,7 @@ 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"
 
