patch 8.2.4217: illegal memory access when undo makes Visual area invalid Commit: https://github.com/vim/vim/commit/8d02ce1ed75d008c34a5c9aaa51b67cbb9d33baa Author: Bram Moolenaar <Bram@vim.org> Date: Tue Jan 25 18:24:00 2022 +0000 patch 8.2.4217: illegal memory access when undo makes Visual area invalid Problem: Illegal memory access when undo makes Visual area invalid. Solution: Correct the Visual area after undo.