diff --git a/src/testdir/dumps/Test_changing_cmdheight_3.dump b/src/testdir/dumps/Test_changing_cmdheight_3.dump
index d652cc6..0adb5c6 100644
--- a/src/testdir/dumps/Test_changing_cmdheight_3.dump
+++ b/src/testdir/dumps/Test_changing_cmdheight_3.dump
@@ -1,8 +1,8 @@
 > +0&#ffffff0@74
-|~+0#4040ff13&| @73
-|[+3#0000000&|N|o| |N|a|m|e|]| @47|0|,|0|-|1| @9|A|l@1
+|[+3&&|N|o| |N|a|m|e|]| @47|0|,|0|-|1| @9|A|l@1
 | +0&&@74
 @75
 @75
 @75
 @75
+@75
diff --git a/src/testdir/dumps/Test_changing_cmdheight_8.dump b/src/testdir/dumps/Test_changing_cmdheight_8.dump
new file mode 100644
index 0000000..1b24f33
--- /dev/null
+++ b/src/testdir/dumps/Test_changing_cmdheight_8.dump
@@ -0,0 +1,8 @@
+> +0&#ffffff0@74
+|~+0#4040ff13&| @73
+|~| @73
+|~| @73
+|~| @73
+|[+3#0000000&|N|o| |N|a|m|e|]| @47|0|,|0|-|1| @9|A|l@1
+|:+0&&|w|i|n|c|m|d| |_| @65
+@75
diff --git a/src/testdir/test_cmdline.vim b/src/testdir/test_cmdline.vim
index 2b81dc0..dfebb40 100644
--- a/src/testdir/test_cmdline.vim
+++ b/src/testdir/test_cmdline.vim
@@ -293,14 +293,13 @@
   " :resize now also changes 'cmdheight' accordingly
   call term_sendkeys(buf, ":set cmdheight+=1\<CR>")
   call VerifyScreenDump(buf, 'Test_changing_cmdheight_2', {})
-  call term_sendkeys(buf, ":set cmdheight-=1\<CR>")
 
   " using more space moves the status line up
   call term_sendkeys(buf, ":set cmdheight+=1\<CR>")
   call VerifyScreenDump(buf, 'Test_changing_cmdheight_3', {})
 
   " reducing cmdheight moves status line down
-  call term_sendkeys(buf, ":set cmdheight-=2\<CR>")
+  call term_sendkeys(buf, ":set cmdheight-=3\<CR>")
   call VerifyScreenDump(buf, 'Test_changing_cmdheight_4', {})
 
   " reducing window size and then setting cmdheight
@@ -312,10 +311,14 @@
   call term_sendkeys(buf, ":call EchoTwo()\<CR>")
   call VerifyScreenDump(buf, 'Test_changing_cmdheight_6', {})
 
-  " decreasing 'cmdheight' doesn't clear the messages that need hit-enter
+  " increasing 'cmdheight' doesn't clear the messages that need hit-enter
   call term_sendkeys(buf, ":call EchoOne()\<CR>")
   call VerifyScreenDump(buf, 'Test_changing_cmdheight_7', {})
 
+  " window commands do not reduce 'cmdheight' to value lower than :set by user
+  call term_sendkeys(buf, "\<CR>:wincmd _\<CR>")
+  call VerifyScreenDump(buf, 'Test_changing_cmdheight_8', {})
+
   " clean up
   call StopVimInTerminal(buf)
 endfunc
diff --git a/src/version.c b/src/version.c
index e8feb96..60de702 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    993,
+/**/
     992,
 /**/
     991,
diff --git a/src/window.c b/src/window.c
index 93b0a32..b15ad3e 100644
--- a/src/window.c
+++ b/src/window.c
@@ -3832,6 +3832,10 @@
     return FALSE;
 }
 
+// 'cmdheight' value explicitly set by the user: window commands are allowed to
+// resize the topframe to values higher than this minimum, but not lower.
+static int min_set_ch = 1;
+
 /*
  * Set a new height for a frame.  Recursively sets the height for contained
  * frames and windows.  Caller must take care of positions.
@@ -3852,9 +3856,11 @@
     if (topfrp->fr_parent == NULL && set_ch)
     {
 	// topframe: update the command line height, with side effects.
-	int new_ch = MAX(1, p_ch + topfrp->fr_height - height);
+	int new_ch = MAX(min_set_ch, p_ch + topfrp->fr_height - height);
+	int save_ch = min_set_ch;
 	if (new_ch != p_ch)
 	    set_option_value((char_u *)"cmdheight", new_ch, NULL, 0);
+	min_set_ch = save_ch;
 	height = MIN(height, ROWS_AVAIL);
     }
     if (topfrp->fr_win != NULL)
@@ -7306,7 +7312,7 @@
 	old_p_ch += h;
 	frp = frp->fr_prev;
     }
-    if (p_ch < old_p_ch && command_frame_height)
+    if (p_ch < old_p_ch && command_frame_height && frp != NULL)
 	frame_add_height(frp, (int)(old_p_ch - p_ch));
 
     // Recompute window positions.
@@ -7325,6 +7331,7 @@
     // GUI starts up, we can't be sure in what order things happen.  And when
     // p_ch was changed in another tab page.
     curtab->tp_ch_used = p_ch;
+    min_set_ch = p_ch;
 }
 
 /*