Update runtime files.
diff --git a/runtime/doc/textprop.txt b/runtime/doc/textprop.txt
index b4aeaf7..3752551 100644
--- a/runtime/doc/textprop.txt
+++ b/runtime/doc/textprop.txt
@@ -1,4 +1,4 @@
-*textprop.txt* For Vim version 8.1. Last change: 2018 Dec 30
+*textprop.txt* For Vim version 8.1. Last change: 2019 Jan 08
VIM REFERENCE MANUAL by Bram Moolenaar
@@ -17,6 +17,7 @@
1. Introduction |text-prop-intro|
2. Functions |text-prop-functions|
+3. When text changes |text-prop-changes|
{Vi does not have text properties}
@@ -113,5 +114,25 @@
prop_remove({props} [, {lnum} [, {lnum-end}]])
remove a text property
+==============================================================================
+3. When text changes *text-prop-changes*
+
+Vim will do its best to keep the text properties on the text where it was
+attached. When inserting or deleting text the properties after the change
+will move accordingly.
+
+When text is deleted and a text property no longer includes any text, it is
+deleted. However, a text property that was defined as zero-width will remain,
+unless the whole line is deleted.
+
+When using replace mode, the text properties stay on the same character
+positions, even though the characters themselves change.
+
+
+When text property columns are not updated ~
+
+- When setting the line with |setline()| or through an interface, such as Lua,
+ Tcl or Python.
+
vim:tw=78:ts=8:noet:ft=help:norl: