Quick update: I haven’t had my phone reboot again. Turning off 5G seems to have fixed it for now.
I do encounter an annoying malfunction since this update. The update itself went smoothly and I can confirm the so much better behaviour in terms of multitasking and not not killing the background apps as aggressively anymore.
However, there is now an issue with opening the camera on double-clicking the power button. I really like and appreciate that function as it offers a quick and intuitive way to access the camera at any time. That is why I have always had this feature turned on in the settings.
Since this latest update (and never before!) my phone seems to accept the fingerprint unlock as the first click. And then the first actualy, physical click on the button is the second click. This misbehaviour brings up the camera all the time I do not want to have it.
Yesterday I was on a full day hike where I usually use an outdoor app for navigation. This app monitors the power button and displays the map on a single push on it without unlocking. It would always bring up the camera instead of the map as my finger first unlocked and then the push was interpreted as second click. So the entire day I had to use an awkward finger that was not registered in the fingerprint sensor to actually open the map.
Am I the only one observing this matter or can anyone confirm this bug?
Edit: And what’s even worse – even a single push on the power button to turn the phone off (=standby) brings up the camera. So I unlock the phone with the fingerprint just to look at something and then want it back to standby, push the button and the camera is on… 
I can def not reproduce this. Whats your setting reg unlock behaviour, can you unlock by just putting (not pushing) the finger on the fingerprint reader?
Do you use double tap to wake? If yes you could add the camera quick setting at the bottom of the lockscreen.
Just wanted to thanks the Fairphone devs for the multitasking fix. Navigating between apps is sooo much better now !
I see the camera opening problem as well, but I still don’t have steps to reproduce, yet.
I’ve enabled double press power button for opening the camera and separate press for activating the phone and then fingerprint read to unlock.