Latest secure kernels available in the repos for 32 and 64 bit architecture (stretch-antiX-17, buster-antiX-19, testing and sid). These kernels should fix issues with ufw/gufw.
5.2.21 (64bit and 32 bit pae and non-pae-486)
4.19.83 (64bit and 32 bit pae and non-pae-486)
4.9.200 (64 bit and 32 bit pae and non-pae-486)
4.4.200 (64 bit and 32 bit pae and non-pae-486)
Users are strongly advised to upgrade.
NB: It seems that there is still an issue with 4.9 kernels and ufw.
If you need to use ufw, upgrade kernel to 4.19.83 or 5.2.21