selecting least broken llfuse version

1.3.6: works on all supported OSes, but not on py39
1.3.7: does not work on FreeBSD, but with py39

requirements.d/fuse.txt

@@ -1,4 +1,4 @@
 # low-level FUSE support library for "borg mount"
 # please see the comments in setup.py about llfuse.
-llfuse<2.0
-
+llfuse >=1.3.4, <1.3.7; python_version <"3.9"  # broken on py39
+llfuse >=1.3.7, <2.0; python_version >="3.9"  # broken on freebsd

setup.py

@@ -83,8 +83,8 @@ install_requires = [
 # if you do not have llfuse, do not require it, most of borgbackup will work.
 extras_require = {
     'fuse': [
-        'llfuse >=1.3, <2.0',
-        'llfuse >=1.3.4, <2.0; python_version >="3.7"',
+        'llfuse >=1.3.4, <1.3.7; python_version <"3.9"',  # broken on py39
+        'llfuse >=1.3.7, <2.0; python_version >="3.9"',  # broken on freebsd
     ],
 }