diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index 0b8fd2c32..bd6789742 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -2041,11 +2041,16 @@ namespace {
                         base += ' ';
                     base += tok->str();
                     tok = tok->next();
-                    // skip template parameters
+                    // add template parameters
                     if (tok && tok->str() == "<") {
-                        tok = tok->findClosingBracket();
-                        if (tok)
-                            tok = tok->next();
+                        const Token* endTok = tok->findClosingBracket();
+                        if (endTok) {
+                            endTok = endTok->next();
+                            while (tok != endTok) {
+                                base += tok->str();
+                                tok = tok->next();
+                            }
+                        }
                     }
                 }
                 baseTypes.insert(base);
diff --git a/test/testsimplifyusing.cpp b/test/testsimplifyusing.cpp
index 272bde012..6074015a1 100644
--- a/test/testsimplifyusing.cpp
+++ b/test/testsimplifyusing.cpp
@@ -72,6 +72,7 @@ private:
         TEST_CASE(simplifyUsing23);
         TEST_CASE(simplifyUsing24);
         TEST_CASE(simplifyUsing25);
+        TEST_CASE(simplifyUsing26); // #11090
 
         TEST_CASE(simplifyUsing8970);
         TEST_CASE(simplifyUsing8971);
@@ -617,6 +618,34 @@ private:
         ASSERT_EQUALS(expected, tok(code));
     }
 
+    void simplifyUsing26() { // #11090
+        const char code[] = "namespace M {\n"
+                            "    struct A;\n"
+                            "    struct B;\n"
+                            "    struct C;\n"
+                            "    template<typename T>\n"
+                            "    struct F {};\n"
+                            "    template<>\n"
+                            "    struct F<B> : F<A> {};\n"
+                            "    template<>\n"
+                            "    struct F<C> : F<A> {};\n"
+                            "}\n"
+                            "namespace N {\n"
+                            "    using namespace M;\n"
+                            "    using A = void;\n"
+                            "}\n";
+        const char expected[] = "namespace M { "
+                                "struct A ; struct B ; struct C ; "
+                                "struct F<C> ; struct F<B> ; struct F<A> ; "
+                                "struct F<B> : F<A> { } ; struct F<C> : F<A> { } ; "
+                                "} "
+                                "namespace N { "
+                                "using namespace M ; "
+                                "} "
+                                "struct M :: F<A> { } ;";
+        ASSERT_EQUALS(expected, tok(code));
+    }
+
     void simplifyUsing8970() {
         const char code[] = "using V = std::vector<int>;\n"
                             "struct A {\n"