4.21.1 - Make libxfconf multithread-safe - I18n: Update po/LINGUAS list - build: Fix typo in optimization level - README.md: Add uninstall info - Update README after switchover to meson - Update also .gitlab-ci.yml - Remove autotools build - common: Fix -Wlogical-op warning - meson-build: Use configure_file() to generate GNU visibility files - I18n: Update po/LINGUAS list - Translation Updates: Arabic, Estonian, Georgian, Occitan (post 1500), Polish, Slovenian, Thai, Uyghur, Vietnamese