diff --git a/src/testdir/dumps/Test_smooth_diff_change_line_1.dump b/src/testdir/dumps/Test_smooth_diff_change_line_1.dump
new file mode 100644
index 0000000..c634f1d
--- /dev/null
+++ b/src/testdir/dumps/Test_smooth_diff_change_line_1.dump
@@ -0,0 +1,20 @@
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diff --git a/src/testdir/dumps/Test_smooth_diff_change_line_2.dump b/src/testdir/dumps/Test_smooth_diff_change_line_2.dump
new file mode 100644
index 0000000..691fe28
--- /dev/null
+++ b/src/testdir/dumps/Test_smooth_diff_change_line_2.dump
@@ -0,0 +1,20 @@
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diff --git a/src/testdir/dumps/Test_smooth_diff_change_line_3.dump b/src/testdir/dumps/Test_smooth_diff_change_line_3.dump
new file mode 100644
index 0000000..c417840
--- /dev/null
+++ b/src/testdir/dumps/Test_smooth_diff_change_line_3.dump
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diff --git a/src/testdir/dumps/Test_smooth_diff_change_line_4.dump b/src/testdir/dumps/Test_smooth_diff_change_line_4.dump
new file mode 100644
index 0000000..b789df3
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+++ b/src/testdir/dumps/Test_smooth_diff_change_line_4.dump
@@ -0,0 +1,20 @@
+|<+0#4040ff13#ffffff0@2| +0#0000000&|a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a||+1&&|<+0#4040ff13&@2| +0#0000000&|a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a
+| +0#0000e05#a8a8a8255@1|b+0#0000000#ffffff0|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| ||+1&&| +0#0000e05#a8a8a8255@1|b+0#0000000#ffffff0|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| 
+| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c||+1&&| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c
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+| +0#0000e05#a8a8a8255@1| +0#0000000#ffffff0|a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b||+1&&| +0#0000e05#a8a8a8255@1| +0#0000000#ffffff0|a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b
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+| +0#0000e05#a8a8a8255@1|b+0#0000000#ffffff0|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| ||+1&&| +0#0000e05#a8a8a8255@1|b+0#0000000#ffffff0|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| 
+| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c||+1&&| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c
+| +0#0000e05#a8a8a8255@1| +0#0000000#ffffff0|a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b||+1&&| +0#0000e05#a8a8a8255@1| +0#0000000#ffffff0|a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b
+| +0#0000e05#a8a8a8255@1|c+0#0000000#ffffff0| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a||+1&&| +0#0000e05#a8a8a8255@1|c+0#0000000#ffffff0| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a
+| +0#0000e05#a8a8a8255@1|b+0#0000000#ffffff0|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| ||+1&&| +0#0000e05#a8a8a8255@1|b+0#0000000#ffffff0|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| 
+| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c||+1&&| +0#0000e05#a8a8a8255@1|a+0#0000000#ffffff0|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c
+| +0#0000e05#a8a8a8255@1| +0#0000000#ffffff0|a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| @14||+1&&| +0#0000e05#a8a8a8255@1| +0#0000000#ffffff0|a|b|c| |a|b|c| |a|b|c| |a|b|c| |a|b|c| @14
+|~+0#4040ff13&| @35||+1#0000000&|~+0#4040ff13&| @35
+|~| @35||+1#0000000&|~+0#4040ff13&| @35
+|~| @35||+1#0000000&|~+0#4040ff13&| @35
+|[+1#0000000&|N|o| |N|a|m|e|]| |[|+|]| @5|3|,|1| @11|A|l@1| |[+3&&|N|o| |N|a|m|e|]| |[|+|]| @5|3|,|1| @11|A|l@1
+| +0&&@74
diff --git a/src/testdir/test_scroll_opt.vim b/src/testdir/test_scroll_opt.vim
index 47a3cf8..9c4e29e 100644
--- a/src/testdir/test_scroll_opt.vim
+++ b/src/testdir/test_scroll_opt.vim
@@ -302,6 +302,36 @@
   call StopVimInTerminal(buf)
 endfunc
 
+func Test_smoothscroll_diff_change_line()
+  CheckScreendump
+
+  let lines =<< trim END
+    set diffopt+=followwrap smoothscroll
+    call setline(1, repeat(' abc', &columns))
+    call setline(2, 'bar')
+    call setline(3, repeat(' abc', &columns))
+    vnew
+    call setline(1, repeat(' abc', &columns))
+    call setline(2, 'foo')
+    call setline(3, 'bar')
+    call setline(4, repeat(' abc', &columns))
+    windo exe "normal! 2gg5\<C-E>"
+    windo diffthis
+  END
+  call writefile(lines, 'XSmoothDiffChangeLine', 'D')
+  let buf = RunVimInTerminal('-S XSmoothDiffChangeLine', #{rows: 20, columns: 55})
+
+  call VerifyScreenDump(buf, 'Test_smooth_diff_change_line_1', {})
+  call term_sendkeys(buf, "Abar")
+  call VerifyScreenDump(buf, 'Test_smooth_diff_change_line_2', {})
+  call term_sendkeys(buf, "\<Esc>")
+  call VerifyScreenDump(buf, 'Test_smooth_diff_change_line_3', {})
+  call term_sendkeys(buf, "yyp")
+  call VerifyScreenDump(buf, 'Test_smooth_diff_change_line_4', {})
+
+  call StopVimInTerminal(buf)
+endfunc
+
 func Test_smoothscroll_wrap_scrolloff_zero()
   CheckScreendump