Update runtime files
diff --git a/runtime/doc/gui.txt b/runtime/doc/gui.txt
index c93a050..decc7bf 100644
--- a/runtime/doc/gui.txt
+++ b/runtime/doc/gui.txt
@@ -1,4 +1,4 @@
-*gui.txt* For Vim version 8.2. Last change: 2021 May 01
+*gui.txt* For Vim version 8.2. Last change: 2021 Jun 27
VIM REFERENCE MANUAL by Bram Moolenaar
@@ -411,7 +411,8 @@
3.7 Drag and drop *drag-n-drop*
You can drag and drop one or more files into the Vim window, where they will
-be opened as if a |:drop| command was used.
+be opened as if a |:drop| command was used. You can check if this is
+supported with the *drop_file* feature: `has('drop_file')`.
If you hold down Shift while doing this, Vim changes to the first dropped
file's directory. If you hold Ctrl Vim will always split a new window for the