Hi all! Good news:
The Libreoffice backport from bookworm seems to fix this issue. I've checked this on different kernels: Besides of the 4.9.0 kernel I've tested this on linux-image-5.10.137-antix.1-686-smp-pae linux-image-5.10.142-antix.2-686-smp-pae linux-image-5.10.0-18-686-pae (signed) linux-image-5.10.0-19-686-pae (signed) and additionally from on most recent one from Bullseye-Backports: linux-image-5.19.0-0.deb11.2-686-pae Really great thing is, that this most recent backport kernel comes up with noveau driver properly now, this is first time I see noveau running mostly equivalent to old proprietary driver stuff from nvidia. Everything efficient, fast and fluent, clear view now. Great work, whoever did this, many thanks! This allows me now to switch to 5.x kernel series finally, dumping old nvidia proprietary driver stuff (which was single way to achieve this result until now). But unfortunately this doesn't fix Libreoffice issue all the same: The most recent Libreoffice bullseye version (not the one from backports) shows the originally described issue on all these kernels listed above. Only the Libreoffice backport doesn't show this behaviour any longer, CPU load from Libreoffice backport (details below) stays perfectly normal when it looses focus. Checked for several hours. Many thanks! Maybe you can transfer the fix to the stable bullseye version, so people can run the default version instead of backports, in order to get security updates (above you've stated there are none on backports, which would be bad). Technical details: Version: 7.4.1.2 / LibreOffice Community Build ID: 40(Build:2) CPU threads: 1; OS: Linux 4.9; UI render: default; VCL: gtk3 Locale: de-DE (de_DE.UTF-8); UI: de-DE Debian package version: 1:7.4.1-1~bpo11+2 Calc: threaded $ apt-cache policy libreoffice* | grep -v '(keine)' | grep -B1 Installiert libreoffice-calc: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-base-core: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-core: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-common: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-draw: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-impress: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-l10n-de: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-style-colibre: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-writer: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-help-de: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-help-common: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-math: Installiert: 1:7.4.1-1~bpo11+2 libreoffice-gtk3: Installiert: 1:7.4.1-1~bpo11+2 ucf: Installiert: 3.0043 libabw-0.1-1: Installiert: 0.1.3-1 libc6: Installiert: 2.31-13+deb11u5 libe-book-0.1-1: Installiert: 0.1.3-2 libepubgen-0.1-1: Installiert: 0.1.1-1 libetonyek-0.1-1: Installiert: 0.1.9-4 libgcc-s1: Installiert: 10.2.1-6 libicu67: Installiert: 67.1-7 libodfgen-0.1-1: Installiert: 0.1.8-2 librevenge-0.0-0: Installiert: 0.0.4-6+b1 libstaroffice-0.0-0: Installiert: 0.0.7-1 libstdc++6: Installiert: 10.2.1-6 libuno-cppu3: Installiert: 1:7.0.4-4+deb11u4 libuno-cppuhelpergcc3-3: Installiert: 1:7.4.1-1~bpo11+2 libuno-sal3: Installiert: 1:7.4.1-1~bpo11+2 libuno-salhelpergcc3-3: Installiert: 1:7.0.4-4+deb11u4 libwpd-0.10-10: Installiert: 0.10.3-1 libwpg-0.3-3: Installiert: 0.3.3-1 libwps-0.4-4: Installiert: 0.4.12-1 libxml2: Installiert: 2.9.10+dfsg-6.7+deb11u2 uno-libs-private: Installiert: 1:7.4.1-1~bpo11+2 zlib1g: Installiert: 1:1.2.11.dfsg-2+deb11u2 fonts-opensymbol: Installiert: 2:102.12+LibO7.4.1-1~bpo11+2 ure: Installiert: 1:7.4.1-1~bpo11+2 $ lsb_release -a No LSB modules are available. Distributor ID: Debian Description: Debian GNU/Linux 11 (bullseye) Release: 11 Codename: bullseye uname -r 4.9.0-326-antix.1-686-smp-pae 5.19.0-0.deb11.2-686-pae and others, see listing in introductional text $ lscpu (same as above) $ free gesamt benutzt frei gemns. Puffer/Cache verfügbar Speicher: 2061064 196896 708752 26012 1155416 1771420 Swap: 2097148 0 2097148 Regards Robin