diff --git a/.serena/memories/critical-info.md b/.serena/memories/critical-info.md
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-You are working on the GitHub project penpot/penpot.
-
-# Working with Penpot Designs
-
-Before working with Penpot designs, call the `high_level_overview` tool of the Penpot MCP server.
-It explains the JavaScript API, which you can use to automate tasks via the `execute_code` tool.
-
-# Critical Memories
-
-* Before creating a commit, read `creating-commits`.
-* When working on the Penpot frontend ...
-  - read the file `frontend/AGENTS.md` for an overview 
-  - to understand the connection between the JavaScript API and the ClojureScript code, read memory `frontend/js-api-to-cljs-binding`.
-  - to understand how to execute ClojureScript code in the Penpot frontend, read memory `frontend/cljs-repl`.
+You are working on the GitHub project penpot/penpot.
+
+# Working with Penpot Designs
+
+Before working with Penpot designs, call the `high_level_overview` tool of the Penpot MCP server.
+It explains the JavaScript API, which you can use to automate tasks via the `execute_code` tool.
+
+# Critical Memories
+
+* Before creating a commit, read `creating-commits`.
+* When working on the Penpot frontend ...
+  - read the file `frontend/AGENTS.md` for an overview 
+  - to understand the connection between the JavaScript API and the ClojureScript code, read memory `frontend/js-api-to-cljs-binding`.
+  - to understand how to execute ClojureScript code in the Penpot frontend, read memory `frontend/cljs-repl`.
+
+# Detecting Frontend Crashes
+
+The Penpot frontend can crash silently from the JS API's perspective: `execute_code` calls return successfully, but 1-2s later the workspace becomes unusable (Internal Error page). 
+The `execute_code` tool then stops working, but `cljs_repl` still works. Use it to detect a crash via `(some? (:exception @app.main.store/state))`.
+For details on handling crashes, read memory `frontend/handling-crashes`.
+
diff --git a/.serena/memories/frontend/handling-crashes.md b/.serena/memories/frontend/handling-crashes.md
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+# Handling Penpot Frontend Crashes
+
+When the Penpot frontend crashes, it usually shows the **Internal Error** page (title text "Something bad happened", class `main_ui_static__download-link`).
+
+A typical error pattern is: Changes go through (JS API, `execute_code`), but about 1-2s later, an `update-file` request hits the backend with the change and gets rejected.
+So be sure to check the status for a crash.
+
+After a crash, `execute_code` is unusable (no instances connected), and any data in `storage` is lost, but `cljs_repl` keeps working!
+
+## 1. Detect the crash
+
+cljs REPL `(some? (:exception @app.main.store/state))` returns `true` when the Internal Error page is showing, 
+`false` on a healthy workspace (and after a successful reload).
+
+## 2. Read the cause
+
+The exception is stored at `(:exception @app.main.store/state)`. Useful keys:
+
+- `:type`, `:code`, `:status` — error class (e.g. `:validation` / `:referential-integrity` / `400`)
+- `:hint`, `:details` — human-readable explanation; `:details` typically contains a vector of validation problems with `:shape-id`, `:page-id`, `:args`, etc.
+- `:uri` — the API endpoint that returned the error (e.g. `update-file`)
+- `:app.main.errors/instance` — the underlying JS Error object
+- `:app.main.errors/trace` — JS stack trace string (only shows the response-handling path, not the dispatch site that produced the bad change)
+
+```
+(let [ex (:exception @app.main.store/state)]
+  (select-keys ex [:type :code :status :hint :details :uri]))
+```
+
+For backend validation errors (`:type :validation`), `:details` is the most informative field — it tells you exactly which shape and which invariant was violated.
+
+## 3. Recover and continue testing
+
+Reload steps:
+1. List tabs with `playwright:browser_tabs` (`action: list`) and find the Penpot workspace tab (URL contains `/#/workspace`, title ends in `- Penpot`).
+2. If it isn't the current tab, select it via `playwright:browser_tabs` (`action: select`, `index: <n>`). The selected tab's URL then appears as "Page URL" in the result.
+3. Reload by calling `playwright:browser_navigate` with that same URL.
+4. Confirm recovery: `(some? (:exception @app.main.store/state))` should now return `false`.
+
+Whether the offending change persists depends on the crash type:
+For **backend-rejected changes** (e.g. `:type :validation`, 4xx on `update-file`), changes are NOT persisted. Reload restores the pre-crash state — safe to retry.