Generated titles have a random language in some cases

I would post the chat that made me realize the issue, but I’m not allowed to post links. Anyways:

I was trying to figure out a good way to construct a method in an open source project I was working on using GPT 4o. My first prompt was a ~30 lines of C++ code followed by a short one-sentence question. Then I noticed that the title generated by ChatGPT was Chinese:

UI改进建议
which translates to:
UI improvement suggestions

It appears that when I start a chat with a code fragment, the algorithm to generate the title falls back to a random language. Though it would still be a decent title if it was English.