diff --git a/src/normal.cc b/src/normal.cc
index c1a084a4..40efc32d 100644
--- a/src/normal.cc
+++ b/src/normal.cc
@@ -1104,6 +1104,7 @@ void join_lines_select_spaces(Context& context, NormalParams)
     if (selections.empty())
         return;
     context.selections_write_only() = std::move(selections);
+    context.selections().merge_consecutive();
     ScopedEdition edition(context);
     context.selections().replace({" "_str});
 }
diff --git a/test/regression/4476-invalid-line-join/cmd b/test/regression/4476-invalid-line-join/cmd
new file mode 100644
index 00000000..ba1947f7
--- /dev/null
+++ b/test/regression/4476-invalid-line-join/cmd
@@ -0,0 +1 @@
+%<a-s><a-S><a-j>
diff --git a/test/regression/4476-invalid-line-join/in b/test/regression/4476-invalid-line-join/in
new file mode 100644
index 00000000..b5e0c3a5
--- /dev/null
+++ b/test/regression/4476-invalid-line-join/in
@@ -0,0 +1,2 @@
+ab
+ac
diff --git a/test/regression/4476-invalid-line-join/out b/test/regression/4476-invalid-line-join/out
new file mode 100644
index 00000000..2b456081
--- /dev/null
+++ b/test/regression/4476-invalid-line-join/out
@@ -0,0 +1 @@
+ab ac