The mysterious official team rolled out a new version specifically to announce that ChatGPT Atlas is being retired, saying they recommend using the built-in browser in the ChatGPT app 😅

But the ChatGPT app's built-in browser obviously isn't enough for daily use, so I went back to Dia. Overall, the experience feels like a smooth transition from ChatGPT Atlas.
I used AmpCode low mode to help with the migration. No problems overall—history, bookmarks, and extension data were all fine. Cookie migration was trickier, though; I had the AI try quite a few approaches.
You can send the prompt below to your agent to handle the migration, or use the skill I've distilled from the process (it's a bit richer than the prompt below).
https://github.com/ChanlerDev/skills/skills/atlas-to-dia-migration/SKILL.md
You can install it with skills: npx skills add chanlerdev/skills --skill atlas-to-dia-migration
P.S. In memory of my Atlas 🪦


P.S. I used AmpCode low mode, with GLM 5.2 as the main model. It did a decent job—from exploring migration approaches to completing the full migration, plus distilling it into a skill, it cost $1.9 in total.

Migrating ChatGPT Atlas to the Dia Browser (with Migration Guide)