patch 8.0.0732: when updating a buffer modeless selection is lost commit https://github.com/vim/vim/commit/80dd3f9d41ce2ff6ab3544cdb266627bbdfc34a6 Author: Bram Moolenaar <Bram@vim.org> Date: Wed Jul 19 12:51:52 2017 +0200 patch 8.0.0732: when updating a buffer modeless selection is lost Problem: When updating a buffer for a callback the modeless selection is lost. Solution: Do not insert or delete screen lines when redrawing for a callback and there is a modeless selection.

Tests for file with some lines ending in CTRL-M, some not

STARTTEST
:set ta tx
:e!
:$-3,$w! test.out
:qa!
ENDTEST

this lines ends in a
this one doesn't
this one does
and the last one doesn't