Basically, the web version of the code editor can’t handle a pull request with 4,000 lines of added code and 4,000 lines of deleted code—
it just won’t load and throws a “pull request error.”
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You can discuss Codex-related issues here, but the official place to report them is the OpenAI Codex GitHub Issues.
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The needs to be added to the issue, this is just a forum and not actively monitored by the OpenAI Codex developers.