SUMMARY System Settings becomes extremely laggy when opening “Notifications” panel (LANGUAGE=zh_CN) STEPS TO REPRODUCE 1. Set system locale to a non-English language: e.g., `export LANGUAGE=zh_CN` 2. Open **System Settings** (`systemsettings`) 3. Navigate to the **Notifications**（aka "通知"） page 4. Observe that the window becomes very laggy and almost unresponsive until switching to another panel 5. CPU usage of `systemsettings` spikes to **100% on one core** 6. Open other settings panels – they work normally OBSERVED RESULT * Notifications panel is extremely slow/unresponsive * `systemsettings` CPU usage spikes to one full core * Terminal output shows repeated messages: ``` qrc:/qt/qml/org/kde/kirigami/layouts/FormLayout.qml:132:5: QML GridLayout: possible QQuickItem::polish() loop qrc:/qt/qml/org/kde/kirigami/layouts/FormLayout.qml:132:5: QML GridLayout: GridLayout called polish() inside updatePolish() of GridLayout ``` * Messages repeat every few seconds while the panel is open EXPECTED RESULT * Notifications panel should open normally without lag or high CPU usage * No repetitive QML polish loop messages ADDITIONAL INFORMATION * Issue is **language-specific**: occurs in multiple non-English locales, including `zh_CN`, `ja_JP`, `ar_SA`, and `ko_KR`. English locales (e.g., `en_US`, `en_GB`) do not trigger the issue. * Issue did **not** exist in Plasma 6.4.3 + Frameworks 6.16.0 * I created a Btrfs snapshot before upgrading. After restoring 6.4.3 snapshot, the issue disappears * Seems to be a regression triggered between Frameworks 6.16 → 6.19, specifically affecting non-English locales * This issue was also discussed on the KDE forum: [System Settings becomes extremely laggy when opening “Notifications” panel](https://discuss.kde.org/t/system-settings-becomes-extremely-laggy-when-opening-notifications-panel/40696) --- SOFTWARE/OS VERSIONS Operating System: Fedora Linux 42 KDE Plasma Version: 6.4.5 KDE Frameworks Version: 6.19.0 Qt Version: 6.9.2 Kernel Version: 6.13.12-200.fc41.x86_64 (64-bit) Graphics Platform: Wayland Processors: 8 × Intel® Core™ i5-10210U CPU @ 1.60GHz Memory: 16 GiB of RAM (15.4 GiB usable) Graphics Processor 1: Intel® UHD Graphics Graphics Processor 2: NVIDIA GeForce MX350 --- **Notes / Possible Causes:** * The QML log messages suggest a **polish() loop in GridLayout** within Kirigami framework * Developer `ngraham` suspects it is triggered by **KDE Frameworks** rather than Plasma itself * Language-specific regression affecting non-English locales
Confirmed with these steps
A possibly relevant merge request was started @ https://invent.kde.org/frameworks/qqc2-desktop-style/-/merge_requests/486
Git commit ed82077889fce696f993a5376c27c13f177d5bb8 by Marco Martin. Committed on 20/10/2025 at 11:03. Pushed by mart into branch 'master'. SpinBox: Make paddings integer to avoid potential polish loops This is not about pixel alignment on fractipnal scaling, but about a quirk adapting QStyle pixelmetrics, that are always integer, with QML items which can potentially have fractional sizes right padding depends from the size - styleitem.editRect.right) which will change the implicit width, which might change the width, which will change the right padding. right padding is always fixed if sizes are integer as styleitem.x + styleitem.width - styleitem.editRect.right is always the same result, but only if styleitem.width is integer, because styleitem.editRect will always be integer This is very visible on the notifications kcm with the chinese language Make sure that leftPadding and rightPadding are always rounded so this won't happen again M +3 -2 org.kde.desktop/SpinBox.qml https://invent.kde.org/frameworks/qqc2-desktop-style/-/commit/ed82077889fce696f993a5376c27c13f177d5bb8
*** Bug 510966 has been marked as a duplicate of this bug. ***