patch 8.2.1820: Vim9: crash when error happens in timer callback Commit: https://github.com/vim/vim/commit/820d55a50bbc8c0ad0505b7e4302a734896b6bab Author: Bram Moolenaar <Bram@vim.org> Date: Sat Oct 10 15:05:23 2020 +0200 patch 8.2.1820: Vim9: crash when error happens in timer callback Problem: Vim9: crash when error happens in timer callback. Solution: Check that current_exception is not NULL. (closes https://github.com/vim/vim/issues/7100)