Possible memory leak when opening QMenu in PyQt5

[Phil Thompson]

On 14/05/2026 13:08, Alexander Stamatov wrote:
> Hello, I am observing a large consistent increase in RAM every time a
> nested QMenu is opened in my PyQt5 application.
> 
> Even with a simplified example using a nested menu and no external
> images, the RAM usage grows with each interaction and does not appear
> to be reclaimed. If you do not nest QMenus, nothing will happen, and
> the memory will be deallocated as expected. I have attached a minimal
> reproducible example and demonstrating the problem, here is the link
> to a video demonstrating it on my pc:
> https://drive.google.com/file/d/1pfactub-1R-gPSmARAOmKe9RgujfQdbx/view?usp=sharing
> 
> To reproduce: Run the script, Double-Middle-click the blue square,
> select one of the options from the inner menu and repeat a few times.
> Finally, observe the console output; the RAM usage increases on each
> open/close cycle, while the Qt object count remains constant.
> 
> Environment: Python 3.13.9, PyQt5 version: 5.15.11, Operating System:
> Windows 11 Pro.
> 
> Is this expected behavior due to internal Qt caching, or is there a
> specific way to ensure these resources are released?

That seems to be a Qt question rather than a PyQt question.

The PyQt side doesn't do much once the GUI is set up. I've attached a 
simplified version of your test which minimises the PyQt involvement as 
much as possible. I would hope(!) that this demonstrates similar 
behaviour.

Phil
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