Framework laptop gen11 doesn't boot, power button off but motherboard has flashing red lights when open

Framework laptop intel gen 11 here.
This afternoon the screen flickered briefly and went dark. The power button light was on. With the screen dark, all I could do was to power it down by holding the power button down for 12 seconds. I think it took more than that, but the power button light went off eventually.
Upon attempting to boot it up, it didn’t. The screen is dark and the power button light is off.
I’ve opened the case to check whether something is the matter, had not done so for years, and found the two side LEDs blinking red. I understand this means it’s still powered. But I can’t power it down in any way. The laptop is cold and the fans are off. The lights don’t blink when the case is on, only when lifted up.
Please advice. What can be done? What’s going on?

Follow the instructions in My Framework Laptop (Intel 11th Gen Intel® Core™) is not powering on

Thank you, I had consulted that already. The only part that applies is:

“If your power button doesn’t light up when pressed
Double check the Touchpad Cable that goes between the Touchpad and the Mainboard. Sometimes this can get pulled out slightly when disassembling and assembling the laptop or setting up the DIY Edition, causing no connection. You should check that both sides of this cable are properly inserted. You can follow the step by step instructions on the Input Cover Replacement Guide to do that. Make sure the cable is fully inserted before powering on.”

Unfortunately the Touchpad Cable is just fine, and there’s no further follow up.

Hm. I guess a full reset: Fully Resetting the Mainboard State - Framework Guides? If that doesn’t work, you’ll have to contact support.

Read my mind. Just did that, and the laptop is working again: I am typing from it.

What the hell has happened?

First, the screen briefly flickered and went off. The power button was illuminated.
Second, I pressed the power button for at least 12 seconds until it went off.
Third: wasn’t rebooting.
Fourth: I’ve reset the mainboard state using the link at Fully Resetting the Mainboard State - Framework Guides

Now all works again. Will it go wrong again? Why did the above happen?

Now that it booted again, I see the battery was at 89%. So it didn’t run out of power.

Is this the RTC Coin Cell battery going bad? Should it be replaced?

Any hints appreciated. This is my main work computer and having it fail just like that has been very stressful.

Hard to tell exactly what the issue could be, but I agree that if the laptop is critical to your work, definitely get a support ticket in ASAP. They won’t be able to get to it until next week, but they will also have a better diagnosis.

Thanks, I have submitted a request for support. I hope it is addressed better than prior ones (weak hinges, still unsolved; and overcurrent on USB-C ports, still unsolved; this early gen11 laptop had a number of rough edges and the framework team pretty much dismissed them as non-issues despite the impact on usability).