diff --git a/tools/btoperator.py b/tools/btoperator.py
index 512b040..13a9c63 100644
--- a/tools/btoperator.py
+++ b/tools/btoperator.py
@@ -715,6 +715,12 @@ class Operator(QMainWindow):
                 continue
             tag = pilots[r]["address"]
             env = QProcessEnvironment.systemEnvironment()
+            # ONE unified build (2026-07-22): the GLASS platform env is what
+            # arms the desktop input stack (PadRIO -> bindings.txt keymap,
+            # clickable cockpit).  Without it the instance boots the DEV
+            # profile and the legacy arrow-drive bridge takes the keyboard
+            # (user-reported: "launched with the wrong keymap again").
+            env.insert("BT_PLATFORM", "glass")
             if self.f_gauges.isChecked():
                 env.insert("BT_DEV_GAUGES", "1")
             if self.f_inside.isChecked():