Plasmashell - high CPU usage (10-15%)

[Pjexaf]

I have Plasma + i3. After some of the latest updates I notice that plasmashell loads around 10-15% CPU instead of 0-3% as it was before.
When I login in KDE+plasma session, CPU usage is Ok, but when I use i3+plasma, cpu usage is too high.
I trying to remove ~/.config dir. After that cpu usage stabilized in 0-3%, but all apps became unthemed (no icons, white backgrounds, strange huge fonts, etc). Applying Global theme not helped.
Seems removing ~/.config dir can be a solution, but how can I recreate theme files after that?

sudo strace -p
shows that plasmashell process spamming that message:
poll([{fd=5, events=POLLIN}, 

Pastebin:
https://pastebin.com/z1zP4dHa

STEPS TO REPRODUCE

1. Install fresh Manjaro KDE
2. Install i3 with the following guide: GitHub - heckelson/i3-and-kde-plasma: How to install the i3 window manager on KDE

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Manjaro kernel 5.10.7-3, 64-bit
(available in About System)
KDE Plasma Version: 5.20.5
KDE Frameworks Version: 5.78.0
Qt Version: 5.15.2

[bogdancovaciu]

All that trouble for something that can be done just by installing krohnkite for tiling … Picom is not better than KWin when comes to KDE Plasma compositor.

[Pjexaf]

I used krohnkite about a half of year and moved to i3 because of bugs in this extension. i3 works very well, but after one of the recent updates plasmashell starting uses more cpu than recently for some reasons… I like KDE apps and infrastructure so I want to use all the benefits of qt and plasma.

[Pjexaf]

I remove setting files according to this post:

How reset all KDE settings?

I used solution from [here was a link] Logout from KDE and run: cd ~/ rm -rf .kde rm -rf .cache/plasmashell* rm -rf .cache/org.kde.dirmodel-qml.kcache rm -rf .cache/kioexec/ .cache/krunner/ .cache/ksycoca5* rm -rf .cache/krunnerbookmarkrunnerfirefoxdbfile.sqlite rm -f .config/plasma* rm -rf .config/kde* cd .local/ rm -rf kate/ kded5/ klipper/ knewstuff3/ kscreen/ konsole/ kwalletd/ ksysguard/ kmail2/ kcookiejar/ kactivitymanagerd/ cd share/ rm -rf dolphin kate kcookiejar kded5 keyri…

And CPU usage stabilized.

[Pjexaf]

Looks like after onther system update plasmashell again started uses huge amount of CPU

.
It strange.
Seems the problem connect with plasma widgets.
When I add the “System Load Viewer” and “Network speed” to my two panels, plasmashell starting uses ~10% CPU