Forked conversations not saving

What version of Codex is running?

0.45

Which model were you using?

gpt-5-codex

What platform is your computer?

Darwin 22.6.0 arm64 arm

What steps can reproduce the bug?

When using double esc (esc esc) to fork a conversation at a previous message turn, the resulting forked conversation is often not saved.

In other words, after
1) forking and sending a message at an earlier message point
2) Ctrl + C to exit out of the conversation
3) Running codex resume to resume the conversation

the forked conversation is not in the list of resumable conversations. I think this tends to happen when the conversation is longer or contains an embedded image. Also, it seems to be deterministic for a given conversation- forking from a defective conversation will not save no matter how many times you try.

What is the expected behavior?

Forked conversations should be saved as a new conversation in the resumable menu without fail.

What do you see instead?

Often, the forked conversation is not saved.

Additional information

_No response_