diff --git a/src/common/serialization/vst3/host-context-proxy.cpp b/src/common/serialization/vst3/host-context-proxy.cpp
index a4fef9f9..39f674d0 100644
--- a/src/common/serialization/vst3/host-context-proxy.cpp
+++ b/src/common/serialization/vst3/host-context-proxy.cpp
@@ -21,10 +21,13 @@ Vst3HostContextProxy::ConstructArgs::ConstructArgs() {}
 Vst3HostContextProxy::ConstructArgs::ConstructArgs(
     Steinberg::IPtr<Steinberg::FUnknown> object,
     std::optional<size_t> owner_instance_id)
-    : owner_instance_id(owner_instance_id), host_application_args(object) {}
+    : owner_instance_id(owner_instance_id),
+      host_application_args(object),
+      plug_interface_support_args(object) {}
 
 Vst3HostContextProxy::Vst3HostContextProxy(const ConstructArgs&& args)
     : YaHostApplication(std::move(args.host_application_args)),
+      YaPlugInterfaceSupport(std::move(args.plug_interface_support_args)),
       arguments(std::move(args)){FUNKNOWN_CTOR}
 
       Vst3HostContextProxy::~Vst3HostContextProxy() {
@@ -44,6 +47,10 @@ Vst3HostContextProxy::queryInterface(Steinberg::FIDString _iid, void** obj) {
         QUERY_INTERFACE(_iid, obj, Steinberg::Vst::IHostApplication::iid,
                         Steinberg::Vst::IHostApplication)
     }
+    if (YaPlugInterfaceSupport::supported()) {
+        QUERY_INTERFACE(_iid, obj, Steinberg::Vst::IPlugInterfaceSupport::iid,
+                        Steinberg::Vst::IPlugInterfaceSupport)
+    }
 
     *obj = nullptr;
     return Steinberg::kNoInterface;
diff --git a/src/common/serialization/vst3/host-context-proxy.h b/src/common/serialization/vst3/host-context-proxy.h
index 7f583310..24fd04fa 100644
--- a/src/common/serialization/vst3/host-context-proxy.h
+++ b/src/common/serialization/vst3/host-context-proxy.h
@@ -18,6 +18,7 @@
 
 #include "../common.h"
 #include "host-context/host-application.h"
+#include "host-context/plug-interface-support.h"
 
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
@@ -32,7 +33,8 @@
  * `IPluginBase::initialize()` we'll keep track of the object instance ID the
  * actual context object belongs to.
  */
-class Vst3HostContextProxy : public YaHostApplication {
+class Vst3HostContextProxy : public YaHostApplication,
+                             public YaPlugInterfaceSupport {
    public:
     /**
      * These are the arguments for constructing a
@@ -56,6 +58,7 @@ class Vst3HostContextProxy : public YaHostApplication {
         std::optional<native_size_t> owner_instance_id;
 
         YaHostApplication::ConstructArgs host_application_args;
+        YaPlugInterfaceSupport::ConstructArgs plug_interface_support_args;
 
         template <typename S>
         void serialize(S& s) {
@@ -64,6 +67,7 @@ class Vst3HostContextProxy : public YaHostApplication {
                       s.value8b(instance_id);
                   });
             s.object(host_application_args);
+            s.object(plug_interface_support_args);
         }
     };
 
diff --git a/src/wine-host/bridges/vst3-impls/host-context-proxy.cpp b/src/wine-host/bridges/vst3-impls/host-context-proxy.cpp
index 220faa58..343e86d1 100644
--- a/src/wine-host/bridges/vst3-impls/host-context-proxy.cpp
+++ b/src/wine-host/bridges/vst3-impls/host-context-proxy.cpp
@@ -93,3 +93,12 @@ Vst3HostContextProxyImpl::createInstance(Steinberg::TUID /*cid*/,
 
     return response;
 }
+
+tresult PLUGIN_API
+Vst3HostContextProxyImpl::isPlugInterfaceSupported(const Steinberg::TUID _iid) {
+    // TODO: Implement
+    std::cerr
+        << "TODO: Implement IPlugInterfaceSupport::isPlugInterfaceSupported()"
+        << std::endl;
+    return Steinberg::kNotImplemented;
+}
diff --git a/src/wine-host/bridges/vst3-impls/host-context-proxy.h b/src/wine-host/bridges/vst3-impls/host-context-proxy.h
index 472ebd02..ca33011f 100644
--- a/src/wine-host/bridges/vst3-impls/host-context-proxy.h
+++ b/src/wine-host/bridges/vst3-impls/host-context-proxy.h
@@ -36,6 +36,10 @@ class Vst3HostContextProxyImpl : public Vst3HostContextProxy {
                                       Steinberg::TUID _iid,
                                       void** obj) override;
 
+    // From `IPlugInterfaceSupport`
+    tresult PLUGIN_API
+    isPlugInterfaceSupported(const Steinberg::TUID _iid) override;
+
    private:
     Vst3Bridge& bridge;
 };
diff --git a/src/wine-host/bridges/vst3.cpp b/src/wine-host/bridges/vst3.cpp
index 81e89898..148e585b 100644
--- a/src/wine-host/bridges/vst3.cpp
+++ b/src/wine-host/bridges/vst3.cpp
@@ -804,10 +804,12 @@ void Vst3Bridge::run() {
                 //      start timers from here.
                 return main_context
                     .run_in_context<tresult>([&]() {
+                        // This static cast is required to upcast to `FUnknown*`
                         return object_instances[request.instance_id]
                             .plugin_base->initialize(
-                                object_instances[request.instance_id]
-                                    .host_context_proxy);
+                                static_cast<YaHostApplication*>(
+                                    object_instances[request.instance_id]
+                                        .host_context_proxy));
                     })
                     .get();
             },
@@ -876,7 +878,10 @@ void Vst3Bridge::run() {
                     module->getFactory().get());
                 assert(factory_3);
 
-                return factory_3->setHostContext(plugin_factory_host_context);
+                // This static cast is required to upcast to `FUnknown*`
+                return factory_3->setHostContext(
+                    static_cast<YaHostApplication*>(
+                        plugin_factory_host_context));
             },
             [&](const YaUnitInfo::GetUnitCount& request)
                 -> YaUnitInfo::GetUnitCount::Response {