[Fluent] Some animations play even when animation effects are disabled in Windows Settings

[aquinn39]

Description

In Settings -> Accessibility -> Visual effects we can disable animations. This applies to all UI frameworks - Forms, WPF, UWP, WinUI, etc. With the WPF Fluent styles, the animations for open a ContextMenu and ComboBox still open. There may be other animations as well, these are just the ones I've observed.

Reproduction Steps

1. Create a new WPF app and enable Fluent themes as detailed here.
2. Add a TextBox and ComboBox (and put some random dummy ComboBoxItems in it) to your UI
3. Go to Settings -> Accessibility -> Visual effects and turn off Animation effects
4. Run the app
5. Right click the TextBox to open it's context menu
6. Click on the ComboBox
7. Observe that both play their opening animations, despite them being disabled in Settings

OR

1. Install the WPF Gallery app - https://apps.microsoft.com/detail/9NDLX60WX4KQ?hl=en-us&gl=AU&ocid=pdpshare
2. Go to Settings -> Accessibility -> Visual effects and turn off Animation effects
3. Use the bar on the left side to view the pages for ComboBox
4. Open the ComboBox
5. Repeat the above for TextBox, but right click the TextBox instead to bring up its ContextMenu
6. Observe the animations playing when they open, even though they shouldn't

Expected behavior

No animations should play when animation effects are turned off in Windows Settings.

Actual behavior

ContextMenu and ComboBox play an animation when they open.

Regression?

Yes, didn't happen before.

Known Workarounds

No response

Impact

Causes apps to disrespect the users' accessibility settings.

Configuration

• .NET runtime 10.0.9, built with SDK 10.0.301 - x64
• Windows 11 version 23H2, build 22631.6199 - x64

Other information

No response

[mmanolova-msft]

It seems these animations have always ignored the accessibility setting — I couldn't find an earlier build where Fluent behaved correctly.

@aquinn39, do you recall a specific build/version where the Fluent theme did honor the animation setting, or was the "didn't happen before" comparison against the classic WPF theme (or another framework such as WinForms/WinUI/UWP)? That would help us decide whether this is a true version regression to bisect, or a long-standing Fluent behavioral gap.

[miloush]

Fluent is a new thing, it would be in there from the beginning.

The other WPF themes respect the settings, see e.g. https://github.com/search?q=repo%3Adotnet%2Fwpf+ComboBoxPopupAnimation+language%3AXML&type=code&l=XML and https://github.com/search?q=repo%3Adotnet%2Fwpf+MenuPopupAnimation+language%3Axml&type=code

[aquinn39]

Yeah I don't know if it ever worked in the Fluent theme, but it does definitely work in the older themes.