[Bug] Screenshot fails with unkown reason

[KelvinNovais]

Bug description

The screenshot sometimes fails with unknown reason. The error is not very descriptive, it just says "Screenshot failed".
The problem usually happens when:

• taking a too big screenshot (almost the whole monitor, or across monitors)
• taking a screenshot on the second monitor.

Maybe another issue: screenshot always fails on a virtual machine (Fedora 41, with Gnome)

More information

OS: Fedora Linux 41
DE: GNOME 47
Running GTK4 test (from this repository), without any modifications. On Flatpak sandbox.

---

Here is an example: I selected almost the whole screen, and the system performs the screenshot successfully. The following image was saved on my disk:

However, the application gets an error (after the screenshot was taken):

(org.gnome.PortalTest.Gtk4:2): Gjs-WARNING **: 17:16:20.759: JS ERROR: Gio.IOErrorEnum: Screenshot failed
_takeScreenshot/<@resource:///org/gnome/PortalTest/Gtk4/js/window.js:666:46
main@resource:///org/gnome/PortalTest/Gtk4/js/main.js:66:24
run@resource:///org/gnome/gjs/modules/script/package.js:207:19
@/app/bin/org.gnome.PortalTest.Gtk4:9:17

If you need more information, please give me a way to get a more verbose debugging.