From d951908e122738c0f86947b7d07d3768928e8309 Mon Sep 17 00:00:00 2001
From: Volodymyr Chernetskyi <volodymyr_chernetskyi@goodyear.com>
Date: Sun, 6 Sep 2026 18:37:28 +0200
Subject: [PATCH] fix(ui2): mouse movement dismisses expanded messages #41732

Problem:
cmd_on_key() tests the key it was handed against the literal string
'<MouseMove>', but at that point "typed" still holds raw key bytes. Thus
the comparison never holds and the branch its own comment describes
is dead. Moving the mouse over an expanded cmdline collapses it.

Solution:
Translate the key once, up front, so every comparison in the function
sees the same form.

AI-assisted
---
 runtime/lua/vim/_core/ui2/messages.lua | 2 +-
 test/functional/ui/messages2_spec.lua  | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/runtime/lua/vim/_core/ui2/messages.lua b/runtime/lua/vim/_core/ui2/messages.lua
index 2de4501193..8c06133e16 100644
--- a/runtime/lua/vim/_core/ui2/messages.lua
+++ b/runtime/lua/vim/_core/ui2/messages.lua
@@ -598,6 +598,7 @@ end
 
 local typed_g = false
 local function cmd_on_key(key, typed)
+  typed = fn.keytrans(typed)
   -- Don't dismiss for non-typed keys and mouse movement. When 'g' is passed (typed
   -- or mapped), wait until the next key to avoid flickering when the pager is opened.
   if not typed_g and (typed == '' or (typed == '<MouseMove>' or typed == 'g' or key == 'g')) then
@@ -611,7 +612,6 @@ local function cmd_on_key(key, typed)
     return
   end
   vim.on_key(nil, ui.ns)
-  typed = fn.keytrans(typed)
 
   -- Check if window was entered and reopen with original config. A shown (but not entered)
   -- pager is dismissed instead; "g<" passes through to reopen and enter it.
diff --git a/test/functional/ui/messages2_spec.lua b/test/functional/ui/messages2_spec.lua
index 49b723dcfd..f1d8ed9fde 100644
--- a/test/functional/ui/messages2_spec.lua
+++ b/test/functional/ui/messages2_spec.lua
@@ -544,6 +544,8 @@ describe('messages2', function()
       baz                                                  |
       {16::}{15:echo} {26:"baz"}                                          |
     ]])
+    -- Moving the mouse does not dismiss the pager.
+    api.nvim_input_mouse('move', '', '', 0, 0, 3)
     -- Subsequent typed commands are appended to the pager.
     feed(':echo "typed append"<CR>')
     screen:expect([[