Only one viewport will update at a time with puffin_egui on Windows 10

**Describe the bug**
The separate native window that appears if I use `puffin_egui::show_viewport_if_enabled` will only update when it's focused. And if it is focused, my main window won't update. So it seems like only one window will update at a time, unless I am clicking and dragging one of the windows.

**To Reproduce**
run the eframe example with `cargo run --example eframe`
click the checkboxes for both "Show profiler window" and "Keep repainting this window"

**Expected behavior**
Both windows should be updating and animating at the same time, even while I am not clicking anything

**Video**
here's a video I recorded of what's going on:
[2024-09-02 14-02-01.webm](https://github.com/user-attachments/assets/ec1330bb-f55a-4f2a-9c0d-223f2ffe6a22)

**Device:**
- OS: Windows 10 Enterprise
- Version: 22H2

**Additional context**
This is very likely an underlying issue with `egui` or with `winit` itself, but I first noticed it in this crate. Should I close this bug, and report it to one of the upstream dependencies?