diff --git a/packages/web/src/main.ts b/packages/web/src/main.ts
index aa863a2..547d916 100644
--- a/packages/web/src/main.ts
+++ b/packages/web/src/main.ts
@@ -2,6 +2,13 @@ import { mount } from "svelte";
 import Announcement from "./Announcement.svelte";
 import * as Sentry from "@sentry/browser";
 
+/** A seat link carries its token in the fragment (#seat=<name>.<token>), and
+ * the history breadcrumb for taking it out of the address bar still names
+ * it, so it is cut from every report before one leaves the browser. */
+function scrub(text: string): string {
+  return text.replace(/(#seat=)[^&#\s"']*/g, "$1…");
+}
+
 // Errors only — no tracing, no replay. Without a DSN baked at build time
 // (VITE_SENTRY_DSN in .env.production) this is entirely inert.
 if (import.meta.env.VITE_SENTRY_DSN) {
@@ -13,6 +20,8 @@ if (import.meta.env.VITE_SENTRY_DSN) {
     // Extensions run their own scripts in the page, and their failures are not ours.
     denyUrls: [/^iabjs:\/\//, /^(chrome|moz|safari(-web)?)-extension:\/\//],
     ignoreErrors: ["Java object is gone"],
+    beforeSend: (event) => JSON.parse(scrub(JSON.stringify(event))),
+    beforeBreadcrumb: (crumb) => JSON.parse(scrub(JSON.stringify(crumb))),
   });
 }