[BUG] Transparent GTK theme crashes the hub

**Describe the bug**
Using a GTK theme that utilizes the alpha channel crashes the hub.

**To Reproduce**
Steps to reproduce the behavior:
1. Install a transparent GTK theme(or create one)
2. Launch Unity Hub Native
3. Crash

**Expected behavior**
It should simply work, even if the app itself doesn't handle transparency properly, it should at least launch.

**Screenshots and/or logs**
[log.txt](https://github.com/user-attachments/files/21196326/log.txt)

**Computer information:**
- OS: Arch

**Additional context**
Transparent theme works on all the other apps just fine: