This debug_assert! is hit when opening the browser's print dialog

Steps to reproduce

• Open any simple web app that uses Winit. For example, a Bevy game (can be reproduced in Bevy's examples, like here: https://bevyengine.org/examples/2D%20Rendering/move-sprite/)
• Open the print dialog of the browser. In Google Chrome, it is File > Print... or pressing Ctrl+P or Cmd+P
• Alternatively, you can call print() in the JS console

Expected behaviour

Printing the pixels of canvas, inside the web, at the exact moment of opening the Print dialog, would be ideal. In fact, it's the current behaviour (+ the panic).

It'd be preferable to not show the canvas at all, or to show it as black, rather than crashing.

Actual behaviour

Printing the current frame kind of works:

But then, it panics with the following stack trace: