diff --git a/aegisub/libaegisub/common/io.cpp b/aegisub/libaegisub/common/io.cpp
index 2baac82c0..e4c54ba52 100644
--- a/aegisub/libaegisub/common/io.cpp
+++ b/aegisub/libaegisub/common/io.cpp
@@ -45,7 +45,7 @@ std::unique_ptr<std::ifstream> Open(fs::path const& file, bool binary) {
 
 Save::Save(fs::path const& file, bool binary)
 : file_name(file)
-, tmp_name(unique_path(file.parent_path()/(file.stem().string() + "_tmp_%%%%." + file.extension().string())))
+, tmp_name(unique_path(file.parent_path()/(file.stem().string() + "_tmp_%%%%" + file.extension().string())))
 {
 	LOG_D("agi/io/save/file") << file;
 	acs::CheckDirWrite(file.parent_path());