Disable row and height animations when removing downloads

tests/visual/main.tsx

@@ -205,5 +205,6 @@ export async function startVisualHarness(
 }
 
 if (typeof window !== "undefined" && typeof document !== "undefined") {
+  if (new URLSearchParams(window.location.search).has("check-removal-motion")) void import("./removal-motion-probe");
   startVisualHarness();
 }

tests/visual/removal-motion-probe.ts

@@ -0,0 +1,18 @@
+let checks = 0;
+let movingChecks = 0;
+const observer = new MutationObserver(() => {
+  const body = document.querySelector(".downloads-table-body");
+  if (!body) return;
+  checks++;
+  const moving = [...body.querySelectorAll<HTMLElement>(".downloads-virtual-row")].some((row) => {
+    const target = Number.parseFloat(row.style.getPropertyValue("--downloads-virtual-row-top"));
+    return Math.abs(new DOMMatrixReadOnly(getComputedStyle(row).transform).m42 - target) > 0.5;
+  });
+  const spacer = body.querySelector<HTMLElement>(".downloads-virtual-spacer");
+  const resizing = spacer && Math.abs(spacer.getBoundingClientRect().height - Number.parseFloat(spacer.style.getPropertyValue("--downloads-virtual-total-height"))) > 0.5;
+  if (moving || resizing) movingChecks++;
+  document.documentElement.dataset.removalMotion = JSON.stringify({ checks, movingChecks });
+});
+observer.observe(document.body, { subtree: true, childList: true, attributes: true, attributeFilter: ["style", "class"] });
+
+export {};