diff --git a/crates/formats/src/html.rs b/crates/formats/src/html.rs
index f1eb1693c..a3d76578c 100644
--- a/crates/formats/src/html.rs
+++ b/crates/formats/src/html.rs
@@ -2435,7 +2435,8 @@ mod tests {
         let html = format!("<p>{}x</p>", "<b><br></b><i><br></i>".repeat(100_000));
         let t = std::time::Instant::now();
         let f = parse(&html);
-        assert!(t.elapsed() < std::time::Duration::from_secs(2), "{:?}", t.elapsed());
+        // About a second on a loaded machine; trimming one span at a time ran past 6 minutes.
+        assert!(t.elapsed() < std::time::Duration::from_secs(20), "{:?}", t.elapsed());
         let texts: Vec<String> = f.blocks.iter().filter_map(|b| if let FBlock::Para(p) = b { Some(p.text()) } else { None }).collect();
         assert_eq!(texts, ["x"]);
     }
diff --git a/crates/formats/src/latex.rs b/crates/formats/src/latex.rs
index a79f3a9f0..d2c35f3cb 100644
--- a/crates/formats/src/latex.rs
+++ b/crates/formats/src/latex.rs
@@ -3264,7 +3264,8 @@ Caf\'e na\"ive \c{c}a \v{s}\'{e} and {\bfseries grouped bold} after.
         let src = format!("\\begin{{tabular}}{{l}}{}x{}\\\\\\end{{tabular}}", "\\multicolumn{1}{c}{".repeat(n), "}".repeat(n));
         let t = std::time::Instant::now();
         let f = parse(&src);
-        assert!(t.elapsed() < std::time::Duration::from_secs(2), "{:?}", t.elapsed());
+        // Under a second on a loaded machine; unwrapping every wrapper took 213 s.
+        assert!(t.elapsed() < std::time::Duration::from_secs(10), "{:?}", t.elapsed());
         assert!(f.blocks.iter().any(|b| matches!(b, FBlock::Table(_))));
         // One or two wrappers, as written in real tables, are still read.
         let f = parse("\\begin{tabular}{ll}\\multicolumn{2}{c}{\\multirow{2}{*}{Both}}\\\\\\end{tabular}");
diff --git a/crates/formats/src/markdown.rs b/crates/formats/src/markdown.rs
index 56d631e7a..9196c1968 100644
--- a/crates/formats/src/markdown.rs
+++ b/crates/formats/src/markdown.rs
@@ -2203,7 +2203,8 @@ mod tests {
         let src = "*_".repeat(200_000);
         let t = std::time::Instant::now();
         let out = inl(&src);
-        assert!(t.elapsed() < std::time::Duration::from_secs(2), "{:?}", t.elapsed());
+        // Under a second on a loaded machine; the backwards search ran past 6 minutes.
+        assert!(t.elapsed() < std::time::Duration::from_secs(10), "{:?}", t.elapsed());
         let text: String = out.iter().filter_map(|i| if let Inline::Text(t, _) = i { Some(t.as_str()) } else { None }).collect();
         assert!(text.chars().all(|c| matches!(c, '*' | '_')), "only delimiters come out");
         // Literal delimiters still take the link of the text before them.
diff --git a/crates/formats/src/model.rs b/crates/formats/src/model.rs
index 61ae4aea5..ccc1f1c0c 100644
--- a/crates/formats/src/model.rs
+++ b/crates/formats/src/model.rs
@@ -1669,7 +1669,8 @@ mod tests {
         p.push_text("  x ", &Fmt::default());
         let t = std::time::Instant::now();
         p.trim();
-        assert!(t.elapsed() < std::time::Duration::from_secs(1), "{:?}", t.elapsed());
+        // A fraction of a second; `Vec::remove(0)` per span ran past 6 minutes.
+        assert!(t.elapsed() < std::time::Duration::from_secs(10), "{:?}", t.elapsed());
         assert_eq!(p.inlines, vec![Inline::Text("x".into(), Fmt::default())]);
         // The first span left keeps its formatting and loses only its leading blanks.
         let mut p = Para::default();
diff --git a/crates/formats/src/sheet.rs b/crates/formats/src/sheet.rs
index e3ff85f29..f7f300812 100644
--- a/crates/formats/src/sheet.rs
+++ b/crates/formats/src/sheet.rs
@@ -1252,7 +1252,8 @@ mod tests {
         let row = vec!["Name".to_string(); 5_000];
         let t = std::time::Instant::now();
         let names = field_names(&row);
-        assert!(t.elapsed() < std::time::Duration::from_secs(2), "{:?}", t.elapsed());
+        // Milliseconds; the old numbering ran past 6 minutes.
+        assert!(t.elapsed() < std::time::Duration::from_secs(10), "{:?}", t.elapsed());
         assert_eq!(names.len(), 5_000);
         assert_eq!(names[0], "Name");
         assert_eq!(names[4_999], "Name 5000");