I can confirm this resolves my issue described above. Just delete the eventcalendar plasmoid and you could still reinstall it at the end of your manjaro update (restart).
Why could eventcalendar create such a big issue?
On a side note, the recent update also gave me headache with Compositor and Latte-dock which is luckily easy to resolve:
System settings > Display configuration > Compositor > uncheck Allow applications to block compositing.
Update (239 packages including a new kernel) installed without a hitch.
Manjaro 20.1, Ryzen TR 3960X, 64GB, AMD Radeon RX5600XT on a Gigabyte Aorus Master rev 1.
Hi there,
hadn’t updated for about two months. Went mostly fine. Ran the update in the Octopi terminal. The screensaver seems to have crashed during the update, locking the session, but thankfully displaying a message informing me how to work around this issue (switch to another tty, log in, loginctl unlock-session 2 , and switch back to gfx tty.
It asked me to replace two packages:
:: Replace calibre-common with community/calibre? [Y/n] y
:: Replace libutil-linux with core/util-linux-libs? [Y/n] y
Other than that, I got a couple of warnings about dependency cycles:
warning: dependency cycle detected:
warning: smbclient will be installed before its cifs-utils dependency
warning: dependency cycle detected:
warning: perl-libwww will be installed before its perl-html-parser dependency
warning: dependency cycle detected:
warning: ruby-irb will be installed before its ruby dependency
warning: dependency cycle detected:
warning: ruby-reline will be installed before its ruby dependency
Error:
(1/2) removing calibre-common
rmdir: failed to remove ‘/usr/lib/calibre/’: Directory not empty
error: command failed to execute correctly
And a couple of warnings about directory permission mismatches
warning: directory permissions differ on /var/lib/AccountsService/icons/
filesystem: 755 package: 775
warning: directory permissions differ on /var/lib/dhcpcd/
filesystem: 700 package: 755
warning: directory permissions differ on /usr/share/hplip/base/pycache/
filesystem: 700 package: 755
warning: directory permissions differ on /usr/share/hplip/base/pexpect/pycache/
filesystem: 777 package: 755
warning: directory permissions differ on /usr/share/hplip/prnt/pycache/
filesystem: 777 package: 755
I was informed that a few isysctl settings were not applied, although I don’t remember manually setting anything in this area.
( 5/30) Applying kernel sysctl settings…
Not setting net/ipv4/conf/all/rp_filter (explicit setting exists).
Not setting net/ipv4/conf/default/rp_filter (explicit setting exists).
Not setting net/ipv4/conf/all/accept_source_route (explicit setting exists).
Not setting net/ipv4/conf/default/accept_source_route (explicit setting exists).
Not setting net/ipv4/conf/all/promote_secondaries (explicit setting exists).
Not setting net/ipv4/conf/default/promote_secondaries (explicit setting exists).
System seems to work ok. Will test reboot after I post this message 
This was the first time in 2 years that an update caused problems.
Update went through normally, restarting the computer as well, the desktop started and when I was about to do something, black screen with my mouse cursor in the middle.
I could also solve it by deleting the plasma folder.
Solved by removing the plasma folder in ~/.local/share
sudo rm -R plasma
Many thanks to the developers for this update.
This finally fixed No irq handler for vector / Failed to start Load/Save Screen Backlight Brightness of backlight:acpi_video0 for me.
see this
boot on USB iso manjaro
do chroot ( sudo manjaro-chroot -a )
check list kernels installed & files /etc/mkinitcpio.d/*.preset
i think you should remove 5.7.preset
and then redo mkinitcpio for others
sudo manjaro-chroot -a
ls /etc/mkinitcpio.d/*.preset
mhwd-kernel -li
rm /etc/mkinitcpio.d/<name57>.preset
mkinitcpio -P
update-grub
exitthen reboot
Having a login-loop problem with GDM post-update. I can get past it by alt-ctrl-F2-ing into a terminal, logging in, and then running startx, which starts gnome just fine. I ran pacdiff before the reboot, so it’s nothing to do with any pacnew files. And I didn’t have any remarkable errors or warnings in pacman.log, Thoughts? Should I reinstall GDM?
One update: systemctl status gdm shows the error gkr-pam: unable to locate daemon control file
P.S. This issue is just on my gnome tablet. My desktop running i3 seems to have no issues.
I used Event Calendar in a Latte dock, so after the update that crashed instead of Plasmashell. I have deleted the local version under ~/.local/share and installed v69 from the AUR, but Latte still crashes…
Edit to add that it works as expected without the Event Calendar widget.
Another edit to specify that I can install v69 from the AUR, add it to my Latte dock and change settings, and Latte crashes only after a reboot.
This issue with Event Calendar is wierd. I haven’t updated Manjaro yet because I’m not near that computer but Event Calendar is working fine on my Arch machine and my EndeavourOS machine. 
At least I’ll be warned when I update on Monday! 
Not familiar with Latte, but see the logs to make sure it is loading the addon from /usr/share/plasma/plasmoids/org.kde.plasma.eventcalendar, or if there are other issues with it other than the ones mentioned above.
System settings > Display configuration > Compositor > uncheck ‘Allow applications to block compositing’. Additionally try to change the Rendering backend to OpenGL 3.1.
Seems to be fine on my side, on Manjaro Cinnamon.
Thanks for replying. latte-dock seems to leave no traces itself in the logs (checked the journal logs via the KSystemlog app that comes with KDE, as well as by running latte in the terminal), so I cannot say for sure where it is loading the widget from, but it has to be the one in /usr/share/plasma/ because I deleted the other version in ~. I tried adding the widget to the dock and changing settings or leaving the defaults before terminating the dock, in both cases it cannot start again. I have also tried creating a regular plasma panel and leaving the widget there, and that seems to work fine even after restarting plasmashell. So the problem is related to Latte.
@Jazz Latte works just fine in my case without the widget, and I don’t see how these compositor settings can help. I did try to change them just in case but there was no difference.
That makes some sense to me: something about using event calendar with Latte. I don’t use Latte hence no problems. Sorry I can’t offer a solution, I’m just tracking the thread before I update on Monday.
Will it update without any errors?
To be 100% sure everything will be alright, try to make your own backup/restore system and make a new backup every time right before each update:
Smooth update on 7 (KDE) computers.
Thank you Manjaro team!
With this update, auto-login stopped working in Cinnamon 
I’ve got the same problem as you.
I have a temporary fix for now.
When you have the black background hold down Ctrl + Alt + F2.
Log in and put in your password.
Than type startx.
It should take you to your gui.
That’s just the temporary fix I don’t know how to fix it permanently yet.
I resolved my issue and described how did I do it here:
$ rm -rf ~/.local/share/plasma/plasmoids/org.kde.plasma.eventcalendar
After the Manjaro update, you may update eventcalendar plasmoid and restart Manjaro.