Add linux/plasma specific location opening

main.go

@@ -10,12 +10,15 @@ import (
 	"log"
 	"net"
 	"net/http"
+	"net/url"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"runtime"
 	"strings"
 	"time"
+
+	"github.com/godbus/dbus/v5"
 )
 
 type allowList []string
@@ -267,6 +270,17 @@ func openFolder(path string) error {
 		cmd := exec.Command("explorer.exe", p)
 		return cmd.Start()
 	case "linux":
+		if isKDESession() {
+			if err := openFolderKDEDBus(path); err == nil {
+				return nil
+			}
+			// Fallback: launching dolphin directly typically forwards to an existing
+			// instance (opening a tab) and avoids portal/session-restore oddities.
+			if err := exec.Command("dolphin", path).Start(); err == nil {
+				return nil
+			}
+		}
+
 		cmd := exec.Command("xdg-open", path)
 		return cmd.Start()
 	default:
@@ -274,6 +288,56 @@ func openFolder(path string) error {
 	}
 }
 
+func isKDESession() bool {
+	// Plasma sets XDG_CURRENT_DESKTOP=KDE. Some setups provide multiple entries.
+	cd := strings.ToLower(strings.TrimSpace(os.Getenv("XDG_CURRENT_DESKTOP")))
+	return strings.Contains(cd, "kde")
+}
+
+// openFolderKDEDBus asks the running file manager (Dolphin on Plasma) to show
+// the folder via D-Bus. This tends to reuse an existing Dolphin window and open
+// a new tab instead of spawning a new window and restoring unrelated session
+// tabs.
+//
+// Note: On Plasma Wayland, reliably forcing the window to the foreground is
+// gated by XDG activation tokens; we do a best-effort activation call but it may
+// be ignored by the compositor.
+func openFolderKDEDBus(path string) error {
+	conn, err := dbus.SessionBus()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	uri := (&url.URL{Scheme: "file", Path: filepath.ToSlash(path)}).String()
+	obj := conn.Object("org.freedesktop.FileManager1", dbus.ObjectPath("/org/freedesktop/FileManager1"))
+	call := obj.Call("org.freedesktop.FileManager1.ShowFolders", 0, []string{uri}, "")
+	if call.Err != nil {
+		return call.Err
+	}
+
+	// Best-effort activation of an existing Dolphin window.
+	if dolphinSvc, _ := findFirstDBusName(conn, "org.kde.dolphin-"); dolphinSvc != "" {
+		app := conn.Object(dolphinSvc, dbus.ObjectPath("/org/kde/dolphin"))
+		_ = app.Call("org.freedesktop.Application.Activate", 0, map[string]dbus.Variant{}).Err
+	}
+
+	return nil
+}
+
+func findFirstDBusName(conn *dbus.Conn, prefix string) (string, error) {
+	var names []string
+	if err := conn.BusObject().Call("org.freedesktop.DBus.ListNames", 0).Store(&names); err != nil {
+		return "", err
+	}
+	for _, n := range names {
+		if strings.HasPrefix(n, prefix) {
+			return n, nil
+		}
+	}
+	return "", nil
+}
+
 func writeJSON(w http.ResponseWriter, status int, resp openResponse) {
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(status)