Objects with shadows draw incorrectly with animations

I have some slide decks in Impress I’ve been using for years that suddenly are having graphics errors during presentations on slides with a mix of animations and shadows. For example, when presenting the only slide in this example presentation, the objects with shadows have the shadowed text redrawn after each animation step:

To mitigate this, I’ve had to manually break the slide apart into multiple smaller animation steps, which is less than ideal if I need to edit any individual frame.

Version information, in case it helps:

Build ID: 00(Build:2)
CPU threads: 8; OS: Linux 5.11; UI render: default; VCL: gtk3
Locale: en-US (en_US.UTF-8); UI: en-US
Ubuntu package version: 1:7.0.5-0ubuntu0.20.10.1
Calc: threaded

OS information, in case it helps:

Pop!_OS 20.10 on a 64-bit system with X11 as the windowing system and GNOME version 3.38.3,