Game Crashs when I "AddWidget" in the PlayerUI

Summary

The Fortnite client crashes instantly when a WidgetBlueprint is added to a
player’s PlayerUI via AddWidget in Verse. The crash occurs on widget
realization (client side), not in the Verse call itself. It reproduces in a
live edit session and in private playtest.

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

UI/Tools

Steps to Reproduce

  1. Have a Verse device that, on a button interaction, calls an Open() function.
  2. Open() calls:
    PlayerUI.AddWidget(Inv, player_ui_slot{ InputMode := ui_input_mode.All })
    PlayerUI.SetFocus(Inv)
    where Inv is a WidgetBlueprint asset.
  3. Launch the session, interact with the button.

Expected Result

The widget is displayed on the player’s screen.

Observed Result

The Fortnite client crashes immediately and the player is disconnected.
Server-side Verse continues running: the logs show all prints completing
(about to AddWidget → Open done → RefreshUI done) followed by the player
leaving and the beacon connection closing. This indicates the crash is
client-side, on widget realization, with no server-side Verse error.

Open() : void =
Print(“INV: Open begin”)
if (not Bound?):
BindEvents()
set Bound = true

Populate the widget BEFORE attaching it (matches wbps_manager / custom_player_ui

order), so a remote player never sees a half-filled widget written across frames.

    if (not Added?, PlayerUI := GetPlayerUI[Owner]):
        Print("INV: about to AddWidget")
        PlayerUI.AddWidget(Inv, player_ui_slot{ InputMode := ui_input_mode.All })
        PlayerUI.SetFocus(Inv)
        set Added = true
    Print("INV: Open done")

    
    SyncHotbarFromNative()
    RefreshUI()

Platform(s)

PC, PS5

Island Code

3337-3051-9938

Upload an image

Video

https://youtu.be/yYWiFy-Ba0s

FORT-1118504 has been created and its status is ‘Unconfirmed’. This is now in a queue to be reproduced and confirmed.

remove the setfocus call and see what happens. You don’t need it anyways.

Also, it’s something in your widget so you’ll have to provide details about that. I’m using this hundreds of times a day during testing and no crashing at all (we do crash for other stuff…, but not this)