[fix] enable web file browsing across control transports, refs #135

apps/desktop/src/gui/runtime/peer_data_callbacks.cpp

@@ -151,7 +151,8 @@ void PeerEventHandler::OnReceiveDataBuffer(
        source_id == runtime->clipboard_label_ ||
        source_id == web_clipboard::kStream))
     return;
-  if (source_id == runtime->control_data_label_ &&
+  // MiniRTC reports the browser's reliable control channel as data-stream.
+  if ((source_id == runtime->control_data_label_ || source_id == kWebControlStream) &&
       runtime->transfers_.HandleBrowser(data, size, handler, remote_id)) return;
   if (source_id == web_clipboard::kStream) {
     runtime->clipboard_.ReceiveWeb(
@@ -463,7 +464,7 @@ void PeerEventHandler::OnReceiveDataBuffer(
   }
 
   if (remote_action.type == ControlType::host_infomation) {
-    if (source_id == runtime->control_data_label_) {
+    if (source_id == runtime->control_data_label_ || source_id == kWebControlStream) {
       runtime->transfers_.SetBrowserSupport(handler, remote_id,
           remote_action.i.supports_file_browser);
     }

apps/desktop/src/gui/runtime/peer_event_handler.cpp

@@ -685,12 +685,12 @@ std::string GuiRuntime::BuildHostInformation(bool advertise_trust,
     LOG_INFO("Local display [{}:{}]", i + 1, action.i.display_list[i]);
   auto message = action.to_json();
   FreeRemoteAction(action);
-  if (advertise_trust) {
-    auto information = nlohmann::json::parse(message);
-    information["device_trust_version"] = 1;
-    message = information.dump();
-  }
-  return message;
+  auto information = nlohmann::json::parse(message);
+  // Older desktop builds advertise native directory RPC, but their Web
+  // control router cannot carry it. Negotiate the Web route independently.
+  information["host_info"]["supports_web_file_browser"] = UserSessionFeaturesAvailable();
+  if (advertise_trust) information["device_trust_version"] = 1;
+  return information.dump();
 }
 
 void GuiRuntime::AnnounceHostCapabilities(const std::string& id) {

apps/desktop/src/platform/windows/gui/application/local_host_application.cpp

@@ -1,6 +1,7 @@
 #include "application/gui_application.h"
 
 #include <SDL3/SDL_timer.h>
+#include <stream_names.h>
 #include <web_clipboard_protocol.h>
 #include <algorithm>
 #include <tuple>
@@ -35,7 +36,7 @@ bool GuiRuntime::ForwardUserSessionData(const std::string& id,
   const bool user_stream = stream == file_label_ || stream == file_feedback_label_ ||
       stream == clipboard_label_ || stream == web_clipboard::kStream;
   Json action;
-  if (stream == control_data_label_ && size <= 65536)
+  if ((stream == control_data_label_ || stream == kWebControlStream) && size <= 65536)
     action = Json::parse(data, data + size, nullptr, false);
   const auto type = action.is_object() ? action.value("type", Json{}) : Json{};
   const bool host_info = type == static_cast<int>(ControlType::host_infomation);
@@ -54,7 +55,9 @@ bool GuiRuntime::ForwardUserSessionData(const std::string& id,
   }
   if (local_gui_ready_ && local_host_ &&
       (user_stream || user_control || host_info || preview || audio)) {
-    if (!local_host_->Send({{"op", "data"}, {"id", id}, {"epoch", epoch}, {"stream", stream},
+    // IPC uses the native label; the Web alias belongs to the SCTP boundary.
+    const auto& forwarded_stream = stream == kWebControlStream ? control_data_label_ : stream;
+    if (!local_host_->Send({{"op", "data"}, {"id", id}, {"epoch", epoch}, {"stream", forwarded_stream},
         {"bytes", Json::binary(std::vector<uint8_t>(data, data + size))}})) {
       LOG_WARN(
           "Cannot forward user-session data on {}; reconnecting local frontend",