diff --git a/apps/ely-pdf/src/output.rs b/apps/ely-pdf/src/output.rs
index 4bdb745..ee96f8a 100644
--- a/apps/ely-pdf/src/output.rs
+++ b/apps/ely-pdf/src/output.rs
@@ -203,6 +203,8 @@ impl Viewer {
             Err(error) => return self.failed(&error, cx),
         }
         let (work, path, revision) = (tab.work.join("export.out"), tab.session.path().map(PathBuf::from), tab.session.revision());
+        // Unsaved edits: the file on disk is not "before".
+        let compared = path.clone().filter(|_| !tab.view.read(cx).modified());
         let opened = target.clone();
         log::info!("pdf: exports {}", if kind == Kind::Text { "text" } else { "an optimized copy" });
         self.read_in(
@@ -214,7 +216,7 @@ impl Viewer {
                 }
                 let bytes = std::fs::read(&work)?;
                 std::fs::remove_file(&work)?;
-                let before = path.as_deref().map(std::fs::metadata).transpose()?.map(|meta| meta.len());
+                let before = compared.as_deref().map(std::fs::metadata).transpose()?.map(|meta| meta.len());
                 ely_files::export(&target, path.as_deref(), &bytes, revision)?;
                 Ok((before, bytes.len() as u64))
             },
diff --git a/apps/ely-pdf/src/tests/output.rs b/apps/ely-pdf/src/tests/output.rs
index 805b0fc..2ed42a2 100644
--- a/apps/ely-pdf/src/tests/output.rs
+++ b/apps/ely-pdf/src/tests/output.rs
@@ -195,3 +195,27 @@ fn a_picture_never_drawn_is_checked_before_an_overwrite() {
     settle(cx, |app| viewer.read(app).active_tab().and_then(|tab| tab.risk) == Some(ely_office::Risk::Repaired));
     assert_eq!(std::fs::read(&path).expect("reads"), bytes, "Save turned into Save As");
 }
+
+#[test]
+fn an_edited_document_does_not_quote_the_files_size() {
+    let dir = tempfile::tempdir().expect("a temp dir");
+    let mut cx = TestAppContext::single();
+    let path = file(dir.path(), "doc.pdf", &[(612.0, 792.0, &["First"])]);
+    let (viewer, cx) = windowed(&mut cx, dir.path(), &[path], true);
+    let view = shown(cx, &viewer);
+    // The window's toasts live on its root.
+    let root = cx.update(|window, app| {
+        let root = ely_ui::document_root(ely_platform::AppId::Pdf, viewer.clone().into(), &ely_ui::commands::FILE, Vec::new(), window, app);
+        viewer.update(app, |viewer, _| viewer.core.root = root.downgrade());
+        root
+    });
+    let note = ely_pdf_engine::NewAnnot { page: 0, shape: ely_pdf_engine::Shape::Note((100.0, 500.0)), rgb: None, contents: "n".into(), author: String::new() };
+    cx.update(|_, app| view.update(app, |view, cx| view.annotate("a note", vec![note], cx)));
+    settle(cx, |app| view.read(app).settled() && view.read(app).modified());
+    let id = cx.update(|_, app| viewer.read(app).core.tabs[0].id);
+    let out = dir.path().join("small.pdf");
+    let how = Optimizing { compress: true, from: 300, to: 150 };
+    cx.update(|_, app| viewer.update(app, |viewer, cx| viewer.write_export(id, Kind::Optimized, how, out.clone(), cx)));
+    let done = cx.update(|_, app| crate::viewer::Viewer::text(app, "pdf.export.done", &[("name", "small.pdf")]));
+    settle(cx, |app| root.read(app).toasts(app).iter().any(|(text, _)| *text == done));
+}
diff --git a/tasks/BUGS.md b/tasks/BUGS.md
index 0c40805..a6ed102 100644
--- a/tasks/BUGS.md
+++ b/tasks/BUGS.md
@@ -45,7 +45,7 @@
 - [x] P-10 预览回复被丢弃时“应用”静默无事 — 预览回复照常交回，版本已变即提示，不显示过期预览
 - [x] P-11 撤销或重做在 MuPDF 侧失败后 worker 的步数不再同步 — 撤销失败后重读历史标记
 - [x] P-12 `unhook` 中途抛出时泄漏保留的对象 — 保留的链接随保留随计数
-- [ ] P-13 优化导出的“之前”大小取磁盘文件而非当前文档
+- [x] P-13 优化导出的“之前”大小取磁盘文件而非当前文档 — 有未保存编辑时不与磁盘文件比大小
 - [ ] P-14 文字块含控制字符时 JSON 回复不可解析
 - [x] D-01 导出或打印对话框开着时关闭其标签即崩溃 — Docs 实现 tab_closed，关标签即撤下其导出对话框；R1 PASS
 - [x] D-02 邮件合并以当前标签为模板，预览后生成的每份都是同一条记录 — 选数据时记下模板标签，预览副本不作模板；R1 测试绕过选 CSV 入口；R2 PASS