diff --git a/extern/pfd-fixed/portable-file-dialogs.h b/extern/pfd-fixed/portable-file-dialogs.h
index 134cc6cf7..6d152670e 100644
--- a/extern/pfd-fixed/portable-file-dialogs.h
+++ b/extern/pfd-fixed/portable-file-dialogs.h
@@ -653,7 +653,7 @@ inline void internal::executor::start(int exit_code)
 inline void internal::executor::start_process(std::vector<std::string> const &command)
 {
     printf("---- WILL EXECUTE:\n");
-    for (std::string& i: command) {
+    for (const std::string& i: command) {
       printf("- %s\n",i.c_str());
     }
     printf("END\n");