fix invalid free

src/core/app_state.zig

@@ -45,7 +45,8 @@ pub const AppState = struct {
         } else null;
 
         if (index) |i| {
-            tab.childrenLoaded.observers.swapRemove(i);
+            const removed = tab.childrenLoaded.observers.swapRemove(i);
+            self.allocator.destroy(removed);
         }
 
         //TODO: remove from tabs

src/core/observable.zig

@@ -12,7 +12,7 @@ pub fn Observable(T: type) type {
         }
 
         pub fn deinit(self: *Self) void {
-            for(self.observers)|o| {
+            for(self.observers.items)|o| {
                 self.allocator.destroy(o);
             }
             self.observers.deinit();