The t-test was renamed in this commit: https://cgit.freedesktop.org/libreoffice/core/commit/?id=7ace16688c503795a5af0c82b63856b1e737aa87 We should change occurrences in the helpcontent as well: https://opengrok.libreoffice.org/search?project=help&q=%22t-test%22&defs=&refs=&path=&hist=&type=
Note: The change in the interface is related to Data - Statistics - t-Test. Help page will change accordingly. Reference to Calc function =TTEST() are left unchanged.
Fixed with http://cgit.freedesktop.org/libreoffice/help/commit/?id=9e89f79476859a19c376f0fdf029cc0600a39179 http://cgit.freedesktop.org/libreoffice/help/commit/?id=e741601dd05236be0f9412d8ba5df5314256d3c4&h=libreoffice-6-0