Strangely, I don’t think that I have ever had this problem (after 3 years+ of use and across both amber and byzantium, the former without encryption, the latter with). I wonder what the difference is / what the trigger is.
Is it fixed in crimson (@carlosgonz ) and, if so, are you (@amarok) willing to flash crimson?
This once happened to me after a quick and easy shutdown from the terminal (a bad idea). Your fix is easier than the one I used, although I don’t know if it will work in every case.
Later, I turned the phone on and when the display didn’t come up, I thought the phone was off. So I set it down and didn’t pick it up for a few weeks. By then, the battery was totally drained. After charging the battery for several days, it stayed dead. So I pulled the battery out, left the power plugged in, and booted the phone that way. With no competition between a very dead battery (a big electrical load) and the phone, the phone booted normally. Then while booted, I pushed the battery in, hoping that the intelligence in the phone would regulate the rate of battery charging. That worked. The phone stayed booted and eventually the battery took a full charge with no damage done.
It happens to me very often.
Then, out of the blue, booting is no problem. After a week or so, that bug is back.
Thats already fixed time ago, but not pushed to byzantium tree. However you can update LNX manually.
How can we do this?
Does it afect regular updates?
Just want to say: me too. I have experienced the same problem (for months). I power off my device every night to save energy (plus the security benefit). The next morning, I sometimes have to try 5 times to get the screen on.
I feel like I have never encountered this problem after a year of using L5 (~6 months L5, ~6 months Liberty Phone).
Is the difference that I try to keep battery charge above 40% as much as possible, and usually battery swap to an externally changed battery when it falls below 40%?
For the first several months I didn’t know to battery swap while plugged in and would frequently power off the device to so the swap, so its not as if I was avoiding on/off cycles.
I do this religiously, too.
I suspected this as well, but after keeping the L5 charged near 90%, I noticed that the boot issues where still there.
So now I drain the battery again before charching.
Install thats binaries and reboot
then sudo apt autoremove, sudo apt-mark hold linux*
Purism
My auto-warn level is set to 30% (and has in the past been set to 20%). And invariably the phone is going on charge after the first time it asks me to put it on charge i.e. with an even lower charge level.
So, as neither of us experiences the problem but we have different charging strategies relative to “40%”, I don’t think that’s the difference.
Other factors to consider:
Thank you. When I’m back home I will test it and keep you updated.
Meanwhile I’m visitging your country. It is hot at the moment.
Thanks, but I don’t like to update the kernel to something I don’t fully understand (phone is my daily driver and I need it to work). I’ll wait until an official patch is released. Thanks anyway for thinking along!
In what part of the country are you that is hot?
Aragon: +30°C
My bad.
I was thinking that you lived in Spain. Sorry for that.
Since I reflashed a couple of days ago, I haven’t once seen the problem with the screen not coming on at boot, despite quite a few power-ons over these two days.
So I wonder what I might have done to the old install that isn’t present in the new install… 
(Other than going from non-LUKS to LUKS.)
I am no longer using L5 Liberty for main phone due the start up problem.
It just got updated with new kernel today June 30, no more updates… same start up problem.
5 times to get started… tried twice same result.
I used to turn of during travel and back on for several hours check mail wait for calls due to the battery drain … not using suspend. Too much of a pain to get started.
Hope someone gets this bug fixed soon OR Crimson is gets to usable state (waiting).
Any way, thanks for recent help and I’ll continue reading forum.
Sincerely D. Spring
My librem 5 was also suffering from this issue, but the issue was always intermittent, happening often and then randomly wouldn’t happen.
Now this issue was happening before I had dropped the phone a couple of times, which I give it credit for barely getting a scratch (although the second time put a crack in the screen), it still functioned as normal, only recently it took a very soft fall onto a carpeted floor by just barely a foot off the ground and the screen popped right out. The glue holding the screen in has totally given up, and although this seems irrelevant it did lead me to discover that the issue with the screen not powering on at random was related to pressure on the screen at the very bottom (above the usb-c port).
If I turn the phone off and on again, the screen will not power on unless I put pressure on the bottom center of the screen.
I can only assume that due to previous overheating in summer months that it may have affected soldered connections within the screen.