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Unable to use ChatGPT-5 on Firefox

Denys replied
nattapongkhwanchai

Hello,

I’m experiencing an issue where I cannot use ChatGPT-5 in Firefox. When I log in and try to select or use GPT-5, nothing loads or functions properly. Other models like GPT-3.5 work normally, but GPT-5 does not respond.

I’ve already tried refreshing the page, clearing cache and cookies, and even disabling extensions — but the problem persists. Could this be a compatibility issue with Firefox? Any advice or support would be appreciated.

Thank you in advance for your help!

Hello, I’m experiencing an issue where I cannot use ChatGPT-5 in Firefox. When I log in and try to select or use GPT-5, nothing loads or functions properly. Other models like GPT-3.5 work normally, but GPT-5 does not respond. I’ve already tried refreshing the page, clearing cache and cookies, and even disabling extensions — but the problem persists. Could this be a compatibility issue with Firefox? Any advice or support would be appreciated. Thank you in advance for your help!

所有回覆 (5)

You mean - in the left sidebar?

Thank you for your reply.

No, I meant directly on the chat.com website. ChatGPT recently introduced a new model — GPT-5 — but when I access the site using Firefox, I only see GPT-4o or older versions available. GPT-5 does not appear as an option at all.

However, when I access the site using a different browser like Chrome or Edge, GPT-5 shows up normally. So I’m wondering if this might be a compatibility issue specifically with Firefox.

Any further advice or suggestions would be greatly appreciated. Thanks again!

Try to use the sidebar. Today it's been advertising Chat GPT-5 to me, so I guess it's default and compatible option.

I’ve checked the left sidebar as well, but GPT-5 still doesn’t show up there either. It only displays GPT-4o and the previous versions.

So it seems like GPT-5 is not available at all when I use Firefox, even though it appears just fine on other browsers. Any idea what might be causing this?

Hi,

Do you still experience the issue? There was a kind of progressive rollout, but now the model should be accessible for everyone.