diff --git a/src/common/generators/plantuml/generator.h b/src/common/generators/plantuml/generator.h
index e21f474e..44877215 100644
--- a/src/common/generators/plantuml/generator.h
+++ b/src/common/generators/plantuml/generator.h
@@ -280,10 +280,12 @@ void generator<C, D>::generate(std::ostream &ostr) const
 
     generate_title(ostr);
 
+    // Generate PlantUML directives before auto generated content
     generate_plantuml_directives(ostr, config.puml().before);
 
     generate_diagram(ostr);
 
+    // Generate PlantUML directives after auto generated content
     generate_plantuml_directives(ostr, config.puml().after);
 
     generate_metadata(ostr);
diff --git a/src/common/model/diagram_filter.cc b/src/common/model/diagram_filter.cc
index d29db4da..3e807d92 100644
--- a/src/common/model/diagram_filter.cc
+++ b/src/common/model/diagram_filter.cc
@@ -346,6 +346,35 @@ tvl::value_t element_filter::match(const diagram &d, const element &e) const
         });
 }
 
+tvl::value_t element_filter::match(
+    const diagram &d, const sequence_diagram::model::participant &p) const
+{
+    using sequence_diagram::model::method;
+    using sequence_diagram::model::participant;
+
+    if (d.type() != diagram_t::kSequence)
+        return {};
+
+    const auto &sequence_model =
+        dynamic_cast<const sequence_diagram::model::diagram &>(d);
+    return tvl::any_of(elements_.begin(), elements_.end(),
+        [&sequence_model, &p](const auto &el) {
+            if (p.type_name() == "method") {
+
+                const auto &m = dynamic_cast<const method &>(p);
+                const auto class_id = m.class_id();
+                const auto &class_participant =
+                    sequence_model.get_participant<participant>(class_id)
+                        .value();
+
+                return el == p.full_name(false) ||
+                    el == class_participant.full_name(false);
+            }
+
+            return el == p.full_name(false);
+        });
+}
+
 element_type_filter::element_type_filter(
     filter_t type, std::vector<std::string> element_types)
     : filter_visitor{type}
diff --git a/src/common/model/diagram_filter.h b/src/common/model/diagram_filter.h
index 81cd25b6..a3b868ae 100644
--- a/src/common/model/diagram_filter.h
+++ b/src/common/model/diagram_filter.h
@@ -180,6 +180,9 @@ struct element_filter : public filter_visitor {
 
     tvl::value_t match(const diagram &d, const element &e) const override;
 
+    tvl::value_t match(const diagram &d,
+        const sequence_diagram::model::participant &p) const override;
+
 private:
     std::vector<common::string_or_regex> elements_;
 };
diff --git a/src/sequence_diagram/generators/mermaid/sequence_diagram_generator.cc b/src/sequence_diagram/generators/mermaid/sequence_diagram_generator.cc
index e35dbb49..9183c894 100644
--- a/src/sequence_diagram/generators/mermaid/sequence_diagram_generator.cc
+++ b/src/sequence_diagram/generators/mermaid/sequence_diagram_generator.cc
@@ -37,7 +37,7 @@ std::string render_participant_name(std::string name)
 
 std::string render_message_text(std::string text)
 {
-    util::replace_all(text, ";", "#59;");
+    util::replace_all(text, ";", "&#59;");
 
     return text;
 }
@@ -481,6 +481,12 @@ void generator::generate_diagram(std::ostream &ostr) const
         if (from_activity_id == 0 || to_activity_id == 0)
             continue;
 
+        if (model().participants().count(from_activity_id) == 0)
+            continue;
+
+        if (model().participants().count(to_activity_id) == 0)
+            continue;
+
         auto message_chains_unique = model().get_all_from_to_message_chains(
             from_activity_id, to_activity_id);
 
@@ -522,6 +528,9 @@ void generator::generate_diagram(std::ostream &ostr) const
         for (const auto &mc : message_chains_unique) {
             const auto from_activity_id = mc.front().from();
 
+            if (model().participants().count(from_activity_id) == 0)
+                continue;
+
             const auto &from =
                 model().get_participant<model::function>(from_activity_id);
 
@@ -547,6 +556,9 @@ void generator::generate_diagram(std::ostream &ostr) const
         if (sf.location_type == location_t::function) {
             common::id_t start_from{0};
             for (const auto &[k, v] : model().sequences()) {
+                if (model().participants().count(v.from()) == 0)
+                    continue;
+
                 const auto &caller = *model().participants().at(v.from());
                 std::string vfrom = caller.full_name(false);
                 if (vfrom == sf.location) {
@@ -566,6 +578,9 @@ void generator::generate_diagram(std::ostream &ostr) const
             // Use this to break out of recurrent loops
             std::vector<common::id_t> visited_participants;
 
+            if (model().participants().count(start_from) == 0)
+                continue;
+
             const auto &from =
                 model().get_participant<model::function>(start_from);
 
diff --git a/src/sequence_diagram/generators/plantuml/sequence_diagram_generator.cc b/src/sequence_diagram/generators/plantuml/sequence_diagram_generator.cc
index 2207c95d..7d97a80e 100644
--- a/src/sequence_diagram/generators/plantuml/sequence_diagram_generator.cc
+++ b/src/sequence_diagram/generators/plantuml/sequence_diagram_generator.cc
@@ -483,6 +483,12 @@ void generator::generate_diagram(std::ostream &ostr) const
         if (from_activity_id == 0 || to_activity_id == 0)
             continue;
 
+        if (model().participants().count(from_activity_id) == 0)
+            continue;
+
+        if (model().participants().count(to_activity_id) == 0)
+            continue;
+
         auto message_chains_unique = model().get_all_from_to_message_chains(
             from_activity_id, to_activity_id);
 
@@ -530,6 +536,9 @@ void generator::generate_diagram(std::ostream &ostr) const
 
             const auto from_activity_id = mc.front().from();
 
+            if (model().participants().count(from_activity_id) == 0)
+                continue;
+
             const auto &from =
                 model().get_participant<model::function>(from_activity_id);
 
@@ -553,6 +562,9 @@ void generator::generate_diagram(std::ostream &ostr) const
         if (sf.location_type == location_t::function) {
             common::id_t start_from{0};
             for (const auto &[k, v] : model().sequences()) {
+                if (model().participants().count(v.from()) == 0)
+                    continue;
+
                 const auto &caller = *model().participants().at(v.from());
                 std::string vfrom = caller.full_name(false);
                 if (vfrom == sf.location) {
@@ -569,6 +581,9 @@ void generator::generate_diagram(std::ostream &ostr) const
                 continue;
             }
 
+            if (model().participants().count(start_from) == 0)
+                continue;
+
             // Use this to break out of recurrent loops
             std::vector<common::id_t> visited_participants;
 
diff --git a/src/sequence_diagram/model/diagram.cc b/src/sequence_diagram/model/diagram.cc
index 176b2253..5edb4220 100644
--- a/src/sequence_diagram/model/diagram.cc
+++ b/src/sequence_diagram/model/diagram.cc
@@ -413,6 +413,8 @@ void diagram::print() const
 
     LOG_TRACE(" --- Activities ---");
     for (const auto &[from_id, act] : sequences_) {
+        if (participants_.count(from_id) == 0)
+            continue;
 
         LOG_TRACE("Sequence id={}:", from_id);