**Title:** Black Zotero Quick Format citation window in LibreOffice on Ubuntu 20.04 with NVIDIA GPU

Hello,

I am experiencing a rendering issue with the Zotero Quick Format citation window in LibreOffice.

**System:**

* Ubuntu 20.04
* GNOME session: ubuntu:GNOME
* Display server: X11
* GPU: NVIDIA Quadro P400
* NVIDIA driver: 470.256.02

**Problem:**
When inserting or editing a citation from LibreOffice, the Zotero Quick Format window is completely black:

* no visible borders or UI elements
* the mouse cursor changes to a text insertion cursor when moved over the black area
* the window appears to be functional underneath, but it is unusable because nothing is rendered

The main Zotero window displays correctly after forcing:

```
GTK_THEME=Adwaita:light
```

but this does **not** fix the Quick Format citation window.

**Versions tested:**

* Zotero 7.0.31: problem occurs
* Zotero 9.0.6: problem occurs

**Troubleshooting already attempted:**

* New Zotero profile → no change
* Zotero safe mode → no change
* `LIBGL_ALWAYS_SOFTWARE=1` → no change
* `--disable-gpu` → no change
* `MOZ_DISABLE_GPU=1` → no change
* `MOZ_WEBRENDER=0` → no change

The issue appears specific to the Quick Format dialog used by the LibreOffice integration.

At the moment, Zotero 9 is unusable for me, so I had to return to Zotero 7.0.31. I would also like to know how to prevent Zotero 7 from automatically updating to Zotero 9 until this rendering issue is fixed.

Is there a known workaround or a setting I could try to fix the Quick Format window rendering?

Thank you.