I also experienced the issue after upgrading from Kubuntu 19.04 to 19.10. I am also using LVM as other posters here. I solved the issue with the usual boot from live ISO + mount/chroot + grub-install.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1848797 Title: After upgrading to 19.10, boot screen shows: "Error: symbol 'grub_file_filters' not found." To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1848797/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
