Changing theme is not very clear due to the shadown applied in the background.

Changing theme is not very clear due to the shadown applied in the background.

In settings, when I change the theme, I'd like to see it how does it feel to look at the main application UI. However, applied shadow makes it hard to recognize the changes coming from the new theme.

It'd be great to have the shadow completely dropped or partially removed for couple seconds after the theme change to allow users to observe how the main UI will look.

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| Field | Value |
| --- | --- |
| App version | 1.1.10 |
| OS | Windows 10.0.26200 |
| Theme | Xotopio |
| Path | /chat |
| Tenure | Week 3 |

从 Settings 的主题更改流程开始，检查主题更改后主应用 UI 的阴影是如何应用的。完成的标准是，阴影在短时间内被完全或部分移除，使用户能够清楚地观察主 UI 中的新主题。

由索引模型根据 Issue 内容生成。