patch 8.1.1575: callbacks may be garbage collected commit https://github.com/vim/vim/commit/75a1a9415b9c207de5a29b25c0d1949c6c9c5c61 Author: Bram Moolenaar <Bram@vim.org> Date: Thu Jun 20 03:45:36 2019 +0200 patch 8.1.1575: callbacks may be garbage collected Problem: Callbacks may be garbage collected. Solution: Set reference in callbacks. (Ozaki Kiichi, closes https://github.com/vim/vim/issues/4564)