diff --git a/test/test.mjs b/test/test.mjs
index abc0fceb2..e35a0e2c6 100644
--- a/test/test.mjs
+++ b/test/test.mjs
@@ -1061,6 +1061,9 @@ async function startBrowser({
       // Disable hardware acceleration (fixes rendering issues, see #15168 and
       // #21272, and environments like GitHub Actions don't expose GPUs anyway).
       "gfx.canvas.accelerated": false,
+      // Disable WebGPU (prevents log spam on Windows, and environments like
+      // GitHub Actions don't expose GPUs anyway).
+      "dom.webgpu.enabled": false,
       // It's helpful to see where the caret is.
       "accessibility.browsewithcaret": true,
       // Disable the newtabpage stuff.