Compare: https://help.libreoffice.org/7.3/en-US/text/scalc/01/func_regex.html?DbPAR=CALC > This function is available since LibreOfficeDev 6.2. https://help.libreoffice.org/7.4/en-US/text/scalc/01/func_regex.html?DbPAR=CALC - no such information. The info was added in bug 123803.
Oh - sorry. The information was moved down to "technical information" section, I must check the whole page.