Let's see what this breaks...

src/input/kbMatrixBase.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include "InputBroker.h"
+#include "concurrency/OSThread.h"
+
+class KbMatrixBase : public Observable<const InputEvent *>, public concurrency::OSThread
+{
+  public:
+    explicit KbMatrixBase(const char *name);
+
+  protected:
+    virtual int32_t runOnce() override;
+
+  private:
+    const char *_originName;
+    bool firstTime = 1;
+    int shift = 0;
+    char key = 0;
+    char prevkey = 0;
+};