Reverting to ChatGPT Classic on Mac: What Changed and a Safe Homebrew Route

For a heavy ChatGPT user, installing the new Mac app can feel like losing years of work. The conversations are still there, but the familiar sidebar has vanished. ChatGPT Projects don't show up. Chats started under Work aren't where they'd be expected. Where an organised workspace used to be, there's a small floating list of recent conversations and several competing ideas of what "work" and "projects" mean.

The first guess is a wrong login. The second is a failed sync. The real explanation is more annoying: nothing is broken, and the app is behaving as designed. One user who tried it removed it in under an hour and went back to ChatGPT Classic. What follows covers what changed, why the new app feels fragmented, how other Mac users reacted, and a safe way to return to the previous version.

What shipped on July 9, 2026

On July 9, 2026, OpenAI released a major redesign of its desktop app for macOS and Windows. It's no mere cosmetic refresh. Three formerly separate experiences now live inside a single application:

• Chat, for ordinary questions and conversation.
• ChatGPT Work, aimed at research tasks, file handling and polished deliverables.
• Codex, the coding side, built for software development and agent-driven programming.

In OpenAI's own words, the release gathers Chat, Work and Codex into one desktop app. The old Codex application became the base of the new product, and the previous ChatGPT desktop app was renamed ChatGPT Classic.

The strategy is easy to understand. OpenAI is plainly aiming past the chatbot toward a workspace that can do research, write code, produce documents, operate a computer, manage repositories and run long tasks. The trouble is that the first release of the combined app doesn't yet feel combined.

The missing sidebar

Many long-time users built their routine around the old left sidebar. It gave constant access to recent conversations, long-running research threads, Projects, personal organising schemes, and the chats people kept reopening and extending.

After the update that navigation is gone. The new app exposes only a handful of recent chats in a floating panel, and reaching anything older takes extra steps instead of a quick scan down a list.

For someone with five casual chats, that's a minor change. For someone with years of research, technical notes, architecture discussions, writing projects and personal planning stored in ChatGPT, it's a big one. The old sidebar was more than a menu. It served as an index to an external brain.

Where did Projects go?

The next worry is about Projects. They haven't been deleted. They remain reachable in a browser and in the older interface. They just aren't represented in the new Mac app the way people expect.

The new sidebar has sections built around tasks, plugins and projects, but those aren't the same thing as the ChatGPT Projects already created. The difference matters. Anyone who has used ChatGPT for a while sees the word "Project" and reasonably expects the same collections of chats, files and instructions they have on the web. Instead, the desktop app brings in separate organising models for Chat, Work and Codex. The three share a window but don't yet act like a single information system.

Work conversations are elsewhere too

Opening ChatGPT Work shows the same pattern: conversations created elsewhere in Work don't appear. This is where "super app" starts to look less like integration and more like co-location. Chat, Work and Codex are presented as parts of one product, yet depending on the mode, users may meet different histories, project structures and sync boundaries.

OpenAI's migration documentation concedes the merge of the three experiences, and adds that Work is still being switched on gradually for eligible accounts.

On the technical side, separate storage and execution models are understandable. Codex can operate on local repositories, terminals and files in ways that ordinary cloud chats can't. As a user experience, though, the split is hard to defend. Putting three products in one app leads people to expect a single history, a single project system, a single navigation model and a clear story about syncing. None of that is delivered yet. The interface has been unified faster than the experience underneath it.

Troubleshooting that goes nowhere

An infrastructure engineer's first instinct is to debug, and the standard checks come up empty:

• Verify the right account is signed in.
• Check the active workspace.
• Sign out and back in.
• Quit the app fully and reopen it.
• Search for older conversations.
• Confirm Projects still appear on the web.
• Hunt for a classic-layout preference.
• Compare how Chat, Work and Codex navigate.

The data is intact, the account is fine, and no migration failed. There's also no switch to bring the old sidebar back. The app hasn't lost any content. It just no longer presents that content the way a workflow depends on. Preserving data isn't the same as preserving a workflow.

What other Mac users reported

The reaction wasn't isolated. After the rollout, users reported frustration and confusion about several things:

• recent chats being harder to reach
• Projects missing from their familiar spot
• custom GPTs becoming harder to see
• extra navigation for routine conversations
• doubt over whether anything had been deleted
• trouble finding or reinstalling ChatGPT Classic

Press coverage described similar complaints from people who felt the redesign removed easy access to Projects, custom GPTs and persistent history. Some developers welcomed the tighter Codex integration, while users focused on conversation saw a serious drop in feature parity.

That split is worth attention. The backlash isn't just resistance to change. People use ChatGPT as fundamentally different products.

Two audiences

One group spends its days in Git repositories, terminals, pull requests, development environments and multi-step coding tasks. For them the new app could be a real step up. OpenAI added richer Codex workflows, including support for multiple repositories, pull-request review, inline editing and wider computer-use abilities.

The other group relies on persistent conversations, research archives, Projects, custom GPTs, writing and planning threads, and navigation that stays predictable. A history spanning technical architecture, platform engineering plans, automation, legal research, travel, creative work and discussions that evolved over months turns the old app into a personal knowledge system.

The new app seems tuned for starting tasks. The old one was tuned for returning to accumulated context. Those are different workflows.

A fair verdict

An easy conclusion is that the new app is terrible. A more accurate one is that it's ambitious, capable and not yet ready to replace every workflow ChatGPT Classic supports.

The vision is strong. Imagine a single desktop environment where an AI can answer questions, dig into a hard topic, draft a polished document, change files on disk, look through a codebase, execute shell commands, review a pull request, drive other desktop apps, and keep a long job running in the background. That's a much bigger idea than a chatbot.

The problem is sequencing. The unified shell arrived before navigation, histories, Projects and sync expectations were unified inside it, so the result feels like three products sharing a title bar.

Why Homebrew rather than an old installer

Reverting could mean digging up an old installer from an internet archive or restoring from backup. Neither is attractive, because archived installers raise real security questions: was the binary captured from the original source, has it been altered, can its integrity be verified, is it still signed and notarised, and is it the version it claims to be?

Homebrew offers a separate cask for the purpose:

chatgpt-classic

OpenAI's own release notes confirm that the previous macOS app is now called ChatGPT Classic and can keep being used without moving to the new one. Installation is one line:

brew install --cask chatgpt-classic

Trusting a package name blindly would be careless, though, so the cask deserves inspection before any credentials go into the app. Start with its metadata:

brew info --cask chatgpt-classic

Homebrew identifies it as the previous OpenAI ChatGPT desktop app and shows that it comes from the official Homebrew cask repository. The raw JSON metadata is the next place to look:

curl https://formulae.brew.sh/api/cask/chatgpt-classic.json

It shows that Homebrew fetches this particular build directly from here:

persistent.oaistatic.com/sidekick/public/

That's OpenAI's own static-content infrastructure, not a random GitHub release, file-sharing site or community mirror. The cask also pins a fixed SHA-256 checksum:

49b33cadd2ec659b76352384f7ebd332a7ec7029663365a9f720f4a251d3b8d1

So Homebrew confirms the downloaded file matches the expected binary before installing it. The only meaningful packaging change is a rename so the old app can sit beside the new one:

ChatGPT.app → ChatGPT Classic.app

The executable isn't rebuilt or patched.

One more check: the code signature

The source and checksum are reassuring, and one more verification is cheap. This command inspects the signature:

codesign -dv --verbose=4 "/Applications/ChatGPT Classic.app"

The relevant output looks like this:

Identifier=com.openai.chat
Authority=Developer ID Application: OpenAI OpCo, LLC (2DC432GLL2)
Authority=Developer ID Certification Authority
Authority=Apple Root CA
TeamIdentifier=2DC432GLL2

That confirms several things. The bundle identifies itself as OpenAI's ChatGPT app. The executable is signed by OpenAI OpCo, LLC. The signature chains up through Apple's Developer ID system. The Team Identifier matches the signing identity. The app uses Apple's hardened runtime, and its bundled resources are cryptographically sealed.

In practice, that means an authentic OpenAI-signed application, fetched from an OpenAI-controlled domain, with integrity checked by Homebrew. That's a far stronger chain of provenance than a stray DMG from an archive or a third-party download site.

Step-by-step restore

1. Quit the new app completely, with the keyboard shortcut below. Closing the window isn't enough.

Command + Q

1. Open Finder, go to Applications and drag the new ChatGPT.app to the Trash. This step is optional for anyone who wants both versions installed.
2. Confirm Homebrew is present. If a version number comes back, carry on. If the command is missing, Homebrew's own install instructions come first.

brew --version

1. Install the cask.

brew install --cask chatgpt-classic

Homebrew places the previous app here:

/Applications/ChatGPT Classic.app

1. Review the cask details again.

brew info --cask chatgpt-classic

For more detail, fetch the JSON:

curl https://formulae.brew.sh/api/cask/chatgpt-classic.json

Check that the download points to OpenAI's persistent.oaistatic.com infrastructure.

1. Verify the signature, redirecting stderr so the output prints.

codesign -dv --verbose=4 "/Applications/ChatGPT Classic.app" 2>&1

Look for this line:

Authority=Developer ID Application: OpenAI OpCo, LLC

Gatekeeper can also assess the app:

spctl --assess --type execute --verbose=4 \
  "/Applications/ChatGPT Classic.app"

A properly notarised app should be accepted.

1. Launch it from the Applications folder. The old sidebar, Projects, conversation history and normal navigation return immediately, and the time spent troubleshooting ChatGPT shrinks to nothing. That's what productivity software should allow.

Which app suits whom

The new app fits people who:

• treat Codex as central to their workflow
• work in repositories and terminals regularly
• want agentic computer-use features
• are comfortable with task-oriented navigation
• value integrated development workflows above the earlier chat organisation

ChatGPT Classic fits people who:

• depend heavily on Projects
• reopen old conversations often
• use the sidebar as a knowledge index
• mainly do research, planning, writing or documentation
• find that Work and Codex add complexity without helping their daily routine

There's no universal winner. The mistake would be pretending both apps serve the same user equally well right now.

What would fix it

The new app needn't give up its direction. It needs a better bridge from the old workflow to the new one. A handful of changes would address most complaints:

• A persistent sidebar option showing the full chronological history, Projects and pinned resources.
• A Project that means the same thing, or is clearly distinguished, across web, mobile, Chat, Work and Codex.
• No need to read migration docs to learn why a Work conversation shows up in one place and not another.
• A supported legacy app that doesn't demand Homebrew knowledge, a backup or an archived installer to find.
• No removal of a mature workflow before its replacement matches it.

Innovation shouldn't leave experienced users feeling lost.

Where this leaves things

Trying the new app was worth it. It shows where OpenAI thinks desktop AI is going, and that future looks exciting. It also clarifies what some users actually need: not another task runner but continuity. They want to dig up a chat from half a year back, reopen a Project, pick an architecture discussion up where it stopped, and count on the system built yesterday looking identical tomorrow. ChatGPT Classic provides that today.

The new super app may well become the better product. Once Chat, Work, Codex, Projects and history behave like one coherent system, it deserves a second look. Until then, a unified icon isn't a unified experience, and for many people ChatGPT Classic is back in the Dock.