Dear all, we have lot of cases reported from Firefox users around the world. Users reported that the menu of the Firefox changing to default ---- installed version. This feature https://support.mozilla.org/en-US/kb/use-firefox-another-language simply not working on current stable and beta Firefox. When the window with languages is closed it immediately forget every languages except default. Workaround is install language version that user would use, but this is not easy way id we need to create all language package version in our global company. affected versions 119.0b1 (64-bit) Thanks for fix.