---
id: "4f25267d-3ba5-4c75-b000-0a0a58dc668e"
name: "Clipboard Write And Cmd+V Fill"
micro_summary: "Failed fill method: clipboard-write then Cmd+V. The accumulator worked but clipboard.writeText never resolved through Runtime.evaluate."
status: "discarded"
see_also: []
scope: "Can a large ChatGPT composer prompt be filled through the system clipboard and a real paste?"
discard_reason: "Page-global accumulation worked and verified byte-exact, but navigator.clipboard.writeText never resolved through Runtime.evaluate, so Cmd+V had nothing to paste. A single-shot insert of the whole payload already preserves order."
---
Intended path: build the payload in a page global across small `Runtime.evaluate` appends, `navigator.clipboard.writeText(window.__p)`, then paste with a real Cmd+V so Lexical handles one paste event in order.

The accumulator step worked and is reusable: appending 900 character `JSON.stringify` literals into `window.__p` verified byte-exact against the source, 12983 characters, `window.__p === <source>` true. The clipboard step hung. `await navigator.clipboard.writeText(...)` through `Runtime.evaluate` with `awaitPromise` never resolved and the call timed out, so nothing ever reached the system clipboard and Cmd+V had nothing to paste.

Not retried, because a working single-shot `Input.insertText` of the whole payload was available and preserves order. If this path is ever needed again, test whether the page holds clipboard-write permission before building on it, and remember that a `Runtime.evaluate` timeout here does not prove the write failed.