crash on startup screen when trying to open file or folder after upgrade to 1.29

I've upgraded visual studio code with flatpak and since then I can't use it any more. It's always crashing when I try to click on "open folder" or "add workspace" etc

If I run vscode from shell in devel mode:
```
sh-4.4$ LANG=C /app/extra/vscode/code
Gtk-Message: 19:53:19.760: Failed to load module "pk-gtk-module"
Gtk-Message: 19:53:19.760: Failed to load module "canberra-gtk-module"
Gtk-Message: 19:53:19.760: Failed to load module "pk-gtk-module"
Gtk-Message: 19:53:19.760: Failed to load module "canberra-gtk-module"
[main 7:53:20 PM] update#setState idle
sh: cannot set terminal process group (-1): Inappropriate ioctl for device
sh: no job control in this shell

(code:119): Gtk-WARNING **: 19:53:24.543: Could not load a pixbuf from icon theme.
This may indicate that pixbuf loaders or the mime database could not be found.
**
Gtk:ERROR:../../gtk/gtkiconhelper.c:494:ensure_surface_for_gicon: assertion failed (error == NULL): Failed to load /run/host/share/icons/Paper/16x16/status/image-missing.png: Error opening file /run/host/share/icons/Paper/16x16/status/image-missing.png: No such file or directory (g-io-error-quark, 1)
Cannot upload crash dump: cannot exec /usr/bin/wget
Server response:
Abandon (core dumped)
```

Any idea ? It was working fine before 1.29.

I try to repair, remove/reinstall etc same results.
Using vscode 1.29 from RPM is working fine.

Version: 1.29.0
Commit: 5f24c93878bd4bc645a4a17c620e2487b11005f9
Date: 2018-11-12T07:42:27.562Z
Electron: 2.0.12
Chrome: 61.0.3163.100
Node.js: 8.9.3
V8: 6.1.534.41
Architecture: x64

Best regards,
Edouard

Commencez par exécuter /app/extra/vscode/code depuis le shell Flatpak et reproduisez l’échec de chargement des icônes GTK lors de l’ouverture d’un dossier ou de l’ajout d’un espace de travail. Comparez cela avec l’installation RPM fonctionnelle ; le travail est terminé lorsque VS Code 1.29 dans Flatpak ouvre les dossiers et les espaces de travail sans planter.

Rédigé par le modèle d'indexation à partir du texte de l'issue.