diff --git a/sites/svelte.dev/src/params/not_json.js b/sites/svelte.dev/src/params/not_json.js
new file mode 100644
index 0000000000..e6ebdce488
--- /dev/null
+++ b/sites/svelte.dev/src/params/not_json.js
@@ -0,0 +1,4 @@
+/** @type {import('@sveltejs/kit').ParamMatcher} */
+export function match(param) {
+	return !/\.json$$/.test(param);
+}
diff --git a/sites/svelte.dev/src/routes/(authed)/repl/[id]/+page.server.js b/sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/+page.server.js
similarity index 100%
rename from sites/svelte.dev/src/routes/(authed)/repl/[id]/+page.server.js
rename to sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/+page.server.js
diff --git a/sites/svelte.dev/src/routes/(authed)/repl/[id]/+page.svelte b/sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/+page.svelte
similarity index 100%
rename from sites/svelte.dev/src/routes/(authed)/repl/[id]/+page.svelte
rename to sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/+page.svelte
diff --git a/sites/svelte.dev/src/routes/(authed)/repl/[id]/AppControls.svelte b/sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/AppControls.svelte
similarity index 100%
rename from sites/svelte.dev/src/routes/(authed)/repl/[id]/AppControls.svelte
rename to sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/AppControls.svelte
diff --git a/sites/svelte.dev/src/routes/(authed)/repl/[id]/UserMenu.svelte b/sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/UserMenu.svelte
similarity index 100%
rename from sites/svelte.dev/src/routes/(authed)/repl/[id]/UserMenu.svelte
rename to sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/UserMenu.svelte
diff --git a/sites/svelte.dev/src/routes/(authed)/repl/[id]/downloadBlob.js b/sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/downloadBlob.js
similarity index 100%
rename from sites/svelte.dev/src/routes/(authed)/repl/[id]/downloadBlob.js
rename to sites/svelte.dev/src/routes/(authed)/repl/[id=not_json]/downloadBlob.js