Split from bug 164608 Open Writer, switch to Tabbed UI (View - User Interface), look at the Tools tab and try to locate Address Book Source. It is present in the .ui file, but not visible in the UI: https://git.libreoffice.org/core/+/899064be931ec4bb0cd5f32f60773980470e18a2/sw/uiconfig/swriter/ui/notebookbar.ui#2138 Already seen in Linux 6.1 bibisect repo. Arch Linux 64-bit Version: 26.2.0.0.alpha0+ (X86_64) / LibreOffice Community Build ID: 12efeaf7b623e865e048fb4a8512a5f08f182760 CPU threads: 8; OS: Linux 6.15; UI render: default; VCL: kf6 (cairo+wayland) Locale: fi-FI (fi_FI.UTF-8); UI: en-US Calc: CL threaded Built on 9 July 2025 Version: 26.2.0.0.alpha0+ (X86_64) / LibreOffice Community Build ID: 12efeaf7b623e865e048fb4a8512a5f08f182760 CPU threads: 2; OS: Windows 11 X86_64 (build 26100); UI render: Skia/Raster; VCL: win Locale: en-US (en_US); UI: en-US Calc: threaded