longer fake middle click for applications that need it (firefox)

firmware/include/config.h

 #define INVERT_SCROLL_Y_AXIS false
 #define SCROLL_REDUCE_SENSITIVITY 10
 #define MIN_SCROLL_SUPPRESS_CLICK 10
+#define MOUSE_FAKE_MIDDLE_CLICK_TIME 10
 
 #define DEBOUNCE_DELAY_MS 5
 

firmware/include/controls.h

     bool button[MOUSE_BUTTONS_COUNT];
     int16_t delta_x, delta_y;
     int16_t scroll_x, scroll_y;
-    bool scroll_lock, fake_middle;
+    bool scroll_lock;
+    uint16_t fake_middle;
     int16_t internal_scroll_x, internal_scroll_y;
 };
 

firmware/src/controls.c

     mouse.scroll_x = 0;
     mouse.scroll_y = 0;
     mouse.scroll_lock = false;
-    mouse.fake_middle = false;
+    mouse.fake_middle = 0;
 
     last_mouse = mouse;
 }
         mouse.internal_scroll_y = 0;
     }
 
-    if (mouse.fake_middle) {
-        mouse.button[MOUSE_MIDDLE] = false;
-        mouse.fake_middle = false;
+    if (mouse.fake_middle > 0) {
+        mouse.fake_middle++;
+        if (mouse.fake_middle > MOUSE_FAKE_MIDDLE_CLICK_TIME) {
+            mouse.fake_middle = 0;
+            mouse.button[MOUSE_MIDDLE] = false;
+        }
     }
 
     if (!mouse.scroll_lock && last_mouse.scroll_lock) {
         if (scroll_sum < MIN_SCROLL_SUPPRESS_CLICK) {
             // fake middle mouse click, user was not scrolling
             mouse.button[MOUSE_MIDDLE] = true;
-            mouse.fake_middle = true;
+            mouse.fake_middle = 1;
         }
     }