News: LibreOffice 6.3 Drops Support for 32-bit Linux Distros
You won’t be able to download and upgrade to LibreOffice 6.3 when it’s released in early August 2019, but old versions remain available (some of which are still supported) for use.
The pseudo-LTS version, LibreOffice 6.1, will continue to get updates for 32-bit Linux desktops for a while longer yet.
Most single-board computers run 64-bit processors, but some run 32-bit operating systems. Most notably, Raspberry Pi running Raspbian. Presumably based off this news, the newest versions of LibreOffice will not run on Raspbian until/unless it is upgraded to 64-bit.