Application hangs when user presses Delete after opening a GtkFileChooserNative when run as a flatpak
Steps to reproduce
Flatpak applications hang when the user presses Delete to remove the suggested filename (except for the file extension) after opening a GtkFileChooserNative. For example:
- In Epiphany, right click on any web page and select Save As to open a GtkFileChooserNative
- Press Delete to delete the initially-selected text
You can also reproduce in Builder by using the Save As command (if you can find it; it's accessible via the teensy downward-pointing arrow just underneath the window menu in the top right), typing any character, and then pressing Backspace.
Note: This bug only occurs when running as a Flatpak.
Current behavior
The file chooser hangs until Epiphany is closed with Ctrl+Q. With Builder, Ctrl+Q doesn't work and I have to kill it using System Monitor.
Expected outcome
I should be able to type a filename and save my file
Version information
GTK+ 3 from GNOME nightly runtime (tested with Epiphany) and the 3.28 stable runtime (tested with Builder)