patch 8.1.0245: calling setline() in TextChangedI autocmd breaks undo commit https://github.com/vim/vim/commit/91d2e783b41ca900bc603b3cb5e083c8a4a33170 Author: Bram Moolenaar <Bram@vim.org> Date: Tue Aug 7 19:05:01 2018 +0200 patch 8.1.0245: calling setline() in TextChangedI autocmd breaks undo Problem: Calling setline() in TextChangedI autocmd breaks undo. (Jason Felice) Solution: Don't save lines for undo when already saved. (closes #3291)

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