Tibo, handle thsottiaux, works on Codex at OpenAI and has been posting one improvement a day, or a usage limit reset, as part of a 28 day series. A reset restores a user's usage allowance early.

Tibo posted early on Saturday, as day 26 of his series, that users can now easily switch between multiple accounts on mobile, with desktop support coming soon. He added that the next two days will be resets, and banked ones, without giving more detail.

The OpenAI Help Center page linked in his post says users can stay signed in to up to two ChatGPT accounts at a time and switch between them without signing out, with only one account active at a time. Switching is available on the web and is rolling out on the iOS and Android apps, under Settings, then Switch account.

According to the page, each account keeps its own chats, memory, files, settings and subscription. Switching does not move chats between accounts, merge billing or combine workspaces. Notifications can arrive for both signed in accounts, and tapping one switches to that account. For accounts managed by an organization, administrators may control whether switching is available.

The OpenAI developer community keeps a thread listing each day of the series, which has included model speedups, usage increases and several full resets of usage limits.

Watch for the desktop version Tibo said is coming soon, and for the two resets he promised for the final days of the series. Users will want to know whether the two account limit grows. Companies with managed workspaces will also look at how administrators control switching. The series ends in two days, so OpenAI may say what comes next for Codex.

Terafab is the name Musk has used for a very large chip factory he wants built to supply AI compute. A mass driver is an electromagnetic launcher that throws payloads using electricity instead of rocket fuel. X Freeze is a fan account that often posts clips of Musk.

X Freeze posted a clip on Saturday in which Elon Musk answers what he called the most ambitious question: what comes after a Terafab. The post sums up his answer as a petawatt scale future built on the Moon.

According to the post, the plan is to use Tesla Optimus robots, humans and local lunar manufacturing to build huge compute infrastructure, then launch it into deep space with electromagnetic mass drivers. Because the Moon has no atmosphere and about one sixth of Earth's gravity, the post says such launchers could reach escape velocity on electricity alone, with no rocket fuel burned on the lunar surface. It frames this as scaling compute by three more orders of magnitude, from terawatt to petawatt, a 1,000 times increase.

The X Freeze post quotes a reply Musk wrote the same morning, saying that launching super intelligence satellites into deep space with a mass driver on the Moon can achieve more than a petawatt per year of capability, which he said would far exceed the best case value of Earth's economy. Musk then reposted the clip. The video itself was first shared in an earlier X Freeze post, so the remarks are not new today, but the idea drew fresh attention.

This is a long range vision, not an announced project, and Musk gave no timeline or cost.

Watch whether Tesla or SpaceX attach any concrete plan, budget or timeline to lunar manufacturing, since today this is a vision rather than a program. Progress on the Terafab chip factory itself is the nearer signal to follow. Engineers and skeptics will likely test the physics and economics of mass drivers and space compute. Any Optimus milestones would also show whether robots could do this kind of work.

Optimus is the humanoid robot Tesla is developing. Tesla Owners Silicon Valley is a fan account that often posts clips of Musk.

Tesla Owners Silicon Valley posted a clip late on Friday of Elon Musk explaining why the hand is the hardest part of building Optimus. Musk reposted it on Saturday.

In the quoted remarks, Musk says that building a humanoid robot has made him think a lot about how the human body works, and more than anything about how incredible human hands are. He notes that almost all the muscles that control the hand are actually in the forearm, pulling the fingers like puppets.

That design point matters for robot builders. Putting the motors that drive the fingers in the forearm, the way the body does, keeps the hand itself light and compact, but it means routing tendons or cables through the wrist. Hands with many independent joints are widely seen as one of the toughest parts of humanoid robots, because useful work like picking up tools or handling small parts depends on fine control and touch.

The post does not say when or where Musk made the remarks, and it gives no new specifications or dates for Optimus. The clip is commentary rather than a product announcement, but it drew wide attention after Musk shared it.

Watch for any new Optimus demonstration that shows the hand doing delicate tasks, which would back up Musk's focus on it. Tesla may share hand specifications, such as the number of moving joints, at a future event or earnings call. Rival humanoid makers are working on the same problem, so comparisons of hand dexterity will be a useful way to judge progress across the field.