# Avalonia 12.1.1

- Product: Avalonia (https://whatsnew.fyi/product/avalonia)
- Vendor: AvaloniaUI
- Date: 2026-07-29
- Version: 12.1.1
- Original notes: https://github.com/AvaloniaUI/Avalonia/releases/tag/12.1.1
- Permalink: https://whatsnew.fyi/product/avalonia/releases/12.1.1

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **added** — Add ToolTip.ShouldUseOverlayLayer attached property
- **added** — Allow single parameter with any type when binding to a method
- **added** — Add UseWaylandWithFallback option
- **added** — Expose AutomationId as resource-id for Android automation
- **fixed** — Fix Dispatcher.ReplaceImplementation
- **fixed** — Reapply cached binding source values during UpdateTarget
- **fixed** — Fix custom-hit-test optimization
- **fixed** — Detach platform input when presentation source closes
- **fixed** — Fix line break enumerator infinite loop
- **fixed** — Fix EGL surface recreation after native handle changes
- **fixed** — Fix stale _usedCache value that wasn't reset properly in compositor
- **fixed** — Properly wire CompositionInterop.IsLost
- **fixed** — Preserve lines at rounded fractional heights
- **fixed** — Correct nested TreeViewItem selection behaviour on pointer release
- **fixed** — Fix issues on SelectingItemsControls when items or control changes visibility
- **fixed** — Stop HotKeyManager from triggering on hidden controls
- **fixed** — Fix SplitView stealing BackRequested when its pane is closed
- **fixed** — Fix CommandBar secondary visibility during overflow open
- **fixed** — Fix AutoCompleteBox popup not closing on focus lost
- **fixed** — Position popup using the screen containing the anchor point

##### What's Changed

###### Enhancements
* Controls – Add `ToolTip.ShouldUseOverlayLayer` attached property by @rabbitism in https://github.com/AvaloniaUI/Avalonia/pull/21830
* XAML – Allow single parameter with any type when binding to a method by @MrJul in https://github.com/AvaloniaUI/Avalonia/pull/21867
* Wayland – Add `UseWaylandWithFallback` by @kekekeks in https://github.com/AvaloniaUI/Avalonia/pull/21734
* Android – Expose `AutomationId` as resource-id for Android automation by @stevemonaco in https://github.com/AvaloniaUI/Avalonia/pull/21780

###### Fixes
* Core – Fix `Dispatcher.ReplaceImplementation` by @kekekeks in https://github.com/AvaloniaUI/Avalonia/pull/21735
* Core – Reapply cached binding source values during `UpdateTarget` by @NathanDrake2406 in https://github.com/AvaloniaUI/Avalonia/pull/21756
* Core – Fix custom-hit-test optimization by @kekekeks in https://github.com/AvaloniaUI/Avalonia/pull/21769
* Core – Detach platform input when presentation source closes by @NathanDrake2406 in https://github.com/AvaloniaUI/Avalonia/pull/21782
* Core – Fix line break enumerator infinite loop by @rabbitism in https://github.com/AvaloniaUI/Avalonia/pull/21808
* Core – Fix EGL surface recreation after native handle changes by @AB901 in https://github.com/AvaloniaUI/Avalonia/pull/21816
* Core – Fix stale `_usedCache` value that wasn't reset properly in compositor by @kekekeks in https://github.com/AvaloniaUI/Avalonia/pull/21823
* Core – Properly wire `CompositionInterop.IsLost` by @kekekeks in https://github.com/AvaloniaUI/Avalonia/pull/21824
* Core – Preserve lines at rounded fractional heights by @NathanDrake2406 in https://github.com/AvaloniaUI/Avalonia/pull/21834
* Controls – Correct nested `TreeViewItem` selection behaviour on pointer release by @TomEdwardsEnscape in https://github.com/AvaloniaUI/Avalonia/pull/21705
* Controls – Fix some issues on `SelectingItemsControls` when items or control changes visibility by @timunie in https://github.com/AvaloniaUI/Avalonia/pull/20798
* Controls – Stop `HotKeyManager` from triggering on hidden controls (#21708) by @1419323749 in https://github.com/AvaloniaUI/Avalonia/pull/21714
* Controls – Fix `SplitView` stealing BackRequested when its pane is closed (#21740) by @gentledepp in https://github.com/AvaloniaUI/Avalonia/pull/21741
* Controls – Fix `CommandBar` secondary visibility during overflow open by @NathanDrake2406 in https://github.com/AvaloniaUI/Avalonia/pull/21742
* Controls – Fix `AutoCompleteBox` popup not closing on focus lost by @MrJul in https://github.com/AvaloniaUI/Avalonia/pull/21749
* Controls – Position popup using the screen containing the anchor point by @MrJul in https://github.com/AvaloniaUI/Avalonia/pull/21750
* Controls – Keep page in `NavigationPage`'s logical tree until animation is complete by @MrJul in https://github.com/AvaloniaUI/Avalonia/pull/21751
* Controls – Fix `SimpleTheme` focus adorner contrast in dark mode by @iamvalenciia in https://github.com/AvaloniaUI/Avalonia/pull/21753
* Controls – Fix `ComboBox` dropdown not scrolling to selected item when opened by @zrt2399 in https://github.com/AvaloniaUI/Avalonia/pull/21764
* Controls – Allow `Grid` shared size groups to shrink by @NathanDrake2406 in https://github.com/AvaloniaUI/Avalonia/pull/21837
* Controls – Fix `ListBox` crash when scrolling after item removal by @NathanDrake2406 in https://github.com/AvaloniaUI/Avalonia/pull/21838
* Controls – Clear `TextBox` undo history on external text updates by @NathanDrake2406 in https://github.com/AvaloniaUI/Avalonia/pull/21839
* Controls – Register `Grid` assigned definition collections with their shared size group by @NathanDrake2406 in https://github.com/AvaloniaUI/Avalonia/pull/21848
* Controls – Initialize `TextBox` command states in constructor by @zrt2399 in https://github.com/AvaloniaUI/Avalonia/pull/21859
* Controls – Fix infinite loop in tab stop search with `TabNavigation=Once` by @maggch97 in https://git

_[Truncated at 4000 characters — full notes: https://github.com/AvaloniaUI/Avalonia/releases/tag/12.1.1]_