Refactor to work with HasPrefix

Resolves: #326 (comment)

common/keyboard.go

@@ -236,7 +236,7 @@ func (k *Keyboard) keyDefinitionFromKey(key keyboardlayout.KeyInput) keyboardlay
 	// e.g. `Control`.
 	// When a key such as `2` is pressed, we must ignore shift
 	// otherwise we would type `@`.
-	isKeyXOrOnShiftLayerAndShiftUsed := (isKeyX(string(key)) || foundInShift) &&
+	isKeyXOrOnShiftLayerAndShiftUsed := (strings.HasPrefix(string(key), "Key") || foundInShift) &&
 		shift != 0 &&
 		srcKeyDef.ShiftKey != ""
 	if isKeyXOrOnShiftLayerAndShiftUsed {
@@ -250,39 +250,6 @@ func (k *Keyboard) keyDefinitionFromKey(key keyboardlayout.KeyInput) keyboardlay
 	return keyDef
 }
 
-func isKeyX(key string) bool {
-	_, ok := map[string]interface{}{
-		"KeyA": nil,
-		"KeyB": nil,
-		"KeyC": nil,
-		"KeyD": nil,
-		"KeyE": nil,
-		"KeyF": nil,
-		"KeyG": nil,
-		"KeyH": nil,
-		"KeyI": nil,
-		"KeyJ": nil,
-		"KeyK": nil,
-		"KeyL": nil,
-		"KeyM": nil,
-		"KeyN": nil,
-		"KeyO": nil,
-		"KeyP": nil,
-		"KeyQ": nil,
-		"KeyR": nil,
-		"KeyS": nil,
-		"KeyT": nil,
-		"KeyU": nil,
-		"KeyV": nil,
-		"KeyW": nil,
-		"KeyX": nil,
-		"KeyY": nil,
-		"KeyZ": nil,
-	}[key]
-
-	return ok
-}
-
 func (k *Keyboard) modifierBitFromKeyName(key string) int64 {
 	switch key {
 	case "Alt":