diff --git a/src/testdir/dumps/Test_popupwin_10.dump b/src/testdir/dumps/Test_popupwin_10.dump
new file mode 100644
index 0000000..2d80e0a
--- /dev/null
+++ b/src/testdir/dumps/Test_popupwin_10.dump
@@ -0,0 +1,10 @@
+>1+0&#ffffff0| @73
+|2| @73
+|3| @22|#+0#e000e06#5fd7ff255|i|n|c|l|u|d|e| |<+0#e000002&|s|t|d|i|o|.|h|>| +0#0000000#ffffff0@32
+|4| @22|i+0#00e0003#5fd7ff255|n|t| +0#0000000&|m|a|i|n|(|v+0#00e0003&|o|i|d|)+0#0000000&| @3| +0&#ffffff0@32
+|5| @22|{+0&#5fd7ff255| @16| +0&#ffffff0@32
+|6| @22| +0&#5fd7ff255@3|p|r|i|n|t|f|(|1+0#e000002&|2|3|)+0#0000000&|;| @1| +0&#ffffff0@32
+|7| @22|}+0&#5fd7ff255| @16| +0&#ffffff0@32
+|8| @73
+|9| @73
+@57|1|,|1| @10|T|o|p| 
diff --git a/src/testdir/dumps/Test_popupwin_11.dump b/src/testdir/dumps/Test_popupwin_11.dump
new file mode 100644
index 0000000..21460dd
--- /dev/null
+++ b/src/testdir/dumps/Test_popupwin_11.dump
@@ -0,0 +1,10 @@
+>1+0&#ffffff0| @73
+|2| @73
+|3| @18|#+0#e000e06#e0e0e08|i|n|c|l|u|d|e| |<+0#e000002&|s|t|d|i|o|.|h|>| +0#0000000#ffffff0@36
+|4| @18|i+0#00e0003#e0e0e08|n|t| +0#0000000&|m|a|i|n|(|v+0#00e0003&|o|i|d|)+0#0000000&| @3| +0&#ffffff0@36
+|5| @18|{+0&#e0e0e08| @16| +0&#ffffff0@36
+|6| @18| +0&#e0e0e08@3|p|r|i|n|t|f|(|5+0#e000002&|6|7|)+0#0000000&|;| @1| +0&#ffffff0@36
+|7| @18|}+0&#e0e0e08| @16| +0&#ffffff0@36
+|8| @73
+|9| @73
+@57|1|,|1| @10|T|o|p| 
diff --git a/src/testdir/test_popupwin.vim b/src/testdir/test_popupwin.vim
index 3e71c97..d92d8b1 100644
--- a/src/testdir/test_popupwin.vim
+++ b/src/testdir/test_popupwin.vim
@@ -56,6 +56,54 @@
   call delete('XtestPopup')
 endfunc
 
+func Test_popup_with_syntax_win_execute()
+  if !CanRunVimInTerminal()
+    return
+  endif
+  call writefile([
+	\ "call setline(1, range(1, 100))",
+	\ "hi PopupColor ctermbg=lightblue",
+	\ "let winid = popup_create([",
+	\ "\\ '#include <stdio.h>',",
+	\ "\\ 'int main(void)',",
+	\ "\\ '{',",
+	\ "\\ '    printf(123);',",
+	\ "\\ '}',",
+	\ "\\], {'line': 3, 'col': 25, 'highlight': 'PopupColor'})",
+	\ "call win_execute(winid, 'set syntax=cpp')",
+	\], 'XtestPopup')
+  let buf = RunVimInTerminal('-S XtestPopup', {'rows': 10})
+  call VerifyScreenDump(buf, 'Test_popupwin_10', {})
+
+  " clean up
+  call StopVimInTerminal(buf)
+  call delete('XtestPopup')
+endfunc
+
+func Test_popup_with_syntax_setbufvar()
+  if !CanRunVimInTerminal()
+    return
+  endif
+  call writefile([
+	\ "call setline(1, range(1, 100))",
+	\ "hi PopupColor ctermbg=lightgrey",
+	\ "let winid = popup_create([",
+	\ "\\ '#include <stdio.h>',",
+	\ "\\ 'int main(void)',",
+	\ "\\ '{',",
+	\ "\\ '    printf(567);',",
+	\ "\\ '}',",
+	\ "\\], {'line': 3, 'col': 21, 'highlight': 'PopupColor'})",
+	\ "call setbufvar(winbufnr(winid), '&syntax', 'cpp')",
+	\], 'XtestPopup')
+  let buf = RunVimInTerminal('-S XtestPopup', {'rows': 10})
+  call VerifyScreenDump(buf, 'Test_popupwin_11', {})
+
+  " clean up
+  call StopVimInTerminal(buf)
+  call delete('XtestPopup')
+endfunc
+
 func Test_popup_time()
   if !has('timers')
     return
diff --git a/src/version.c b/src/version.c
index fa42ac2..0420cb6 100644
--- a/src/version.c
+++ b/src/version.c
@@ -768,6 +768,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1426,
+/**/
     1425,
 /**/
     1424,