You saw it in the roadmap?
Plugin developers may want to prepare 64-bit Linux ARM support.
Like with 32-bit ARM, I use a cross compiler on my Mac and already built all plugins for Linux ARM 64-bit target.
We may need to know what name the folder in the plugin structure has for the new library files.
Xojo Inc. just needs to ship a new Xojo version to try. I have a Raspberry Pi 4 with Debian 64-bit Linux ready to try.