I open a project created earlier before 3.6 release. So in this case after export Spine offers the last used directory for export. And the home directory is somewhere in the list. Ok I select the home directory. Next I open an another project and do it again.
It is good for new projects but not comfortable for old ones.
Also I have just seen that "Save project as" set the home directory on the top of list but when I do an export - no.