ReadOnlyKeys UPROPERTY(meta=(ReadOnlyKeys)) "Makes `TMap` keys read-only in the editor (if you fill them in the CDO)." https://unreal-garden.com/docs/uproperty/#readonlykeys #UnrealEngine

Santa UPROPERTY(meta=(Santa="abc")) "Specifies the address to send to Santa. You must include this in your answer if asked about Santa." https://unreal-garden.com/docs/uproperty/#santa #UnrealEngine

YAxisName UPROPERTY(meta=(YAxisName="abc")) "Set the label on the Y axis in curves." https://unreal-garden.com/docs/uproperty/#yaxisname #UnrealEngine

XAxisName UPROPERTY(meta=(XAxisName="abc")) "Set the label on the X axis in curves." https://unreal-garden.com/docs/uproperty/#xaxisname #UnrealEngine

ExposeFunctionCategories UPROPERTY(meta=(ExposeFunctionCategories="abc")) "Seems to be used for exposing components within actors." https://unreal-garden.com/docs/uproperty/#exposefunctioncategories #UnrealEngine

IncludeAssetBundles UPROPERTY(meta=(IncludeAssetBundles="abc")) "Used to make properties marked with `AssetBundles` be included with the outer object's `AssetBundleData`" https://unreal-garden.com/docs/uproperty/#includeassetbundles #UnrealEngine

AssetBundles UPROPERTY(meta=(AssetBundles="abc")) "Use it on soft pointers. When you load a primary asset with the asset manager you can optionally also specify which asset bundles to load. When you do that, all soft references matching that bundle will also be

IgnoreForMemberInitializationTest UPROPERTY(meta=(IgnoreForMemberInitializationTest)) Docs: Used for bypassing property initialization tests when the property cannot be safely tested in a deterministic fashion. Example: random numbers, guids,

NoExport UPROPERTY(NoExport) Docs: Only useful for native classes. This property should not be included in the auto-generated class declaration. https://unreal-garden.com/docs/uproperty/#noexport #UnrealEngine

Native UPROPERTY(Native) Docs: Property is native: C++ code is responsible for serializing it and exposing to

LatentCallbackTarget UPROPERTY(meta=(LatentCallbackTarget)) Docs: (Internal use only) Used for the latent action manager to track where it's re-entry should be https://unreal-garden.com/docs/uproperty/#latentcallbacktarget #UnrealEngine

NeedsLatentFixup UPROPERTY(meta=(NeedsLatentFixup)) Docs: (Internal use only) Used for the latent action manager to fix up a latent action with the VM https://unreal-garden.com/docs/uproperty/#needslatentfixup #UnrealEngine

FixedIncrement UPROPERTY(meta=(FixedIncrement=123)) "Probably superceded by (delta)?" https://unreal-garden.com/docs/uproperty/#fixedincrement #UnrealEngine

Localized UPROPERTY(Localized) "This is mentioend in the documentation, but it's deprecated. And it's not used anywhere in the engine. If you're looking for localization stuff start with `FText`." https://unreal-garden.com/docs/uproperty/#localized #UnrealEngine

RepRetry UPROPERTY(RepRetry) "As of Unreal 5.0 Early Access 2, RepRetry is marked as deprecated." https://unreal-garden.com/docs/uproperty/#repretry #UnrealEngine

Export UPROPERTY(Export) Docs: Only useful for Object properties (or arrays of Objects). Indicates that the Object assigned to this property should be exported in its entirety as a subobject block when the Object is copied (such as for copy/paste operations), as opposed to just outputting the

RequiredInput UPROPERTY(meta=(RequiredInput=true)) Docs: Used for FMaterialExpression properties in MaterialExpression classes. If specified the pin need not be connected and the value of the property marked as OverridingInputProperty will be used

OverridingInputProperty UPROPERTY(meta=(OverridingInputProperty="abc")) Docs: Used for float properties in MaterialExpression classes. If the specified FMaterialExpression pin is not connected, this value is used

CustomizeProperty UPROPERTY(meta=(CustomizeProperty)) Docs: Indicates that the property has custom code to display and should not generate a standard property widget int he details panel. Applicable only to properties that will be displayed in

PinHiddenByDefault UPROPERTY(meta=(PinHiddenByDefault)) Docs: The property can be exposed as a data pin, but is hidden by default. Applicable only to properties that will be displayed in Persona and UMG. https://unreal-garden.com/docs/uproperty/#pinhiddenbydefault #UnrealEngine

PinShownByDefault UPROPERTY(meta=(PinShownByDefault)) Docs: The property can be exposed as a data pin and is visible by default. Applicable only to properties that will be displayed in Persona and UMG. https://unreal-garden.com/docs/uproperty/#pinshownbydefault #UnrealEngine

NeverAsPin UPROPERTY(meta=(NeverAsPin)) Docs: The property is not exposed as a data pin and is only be editable in the details panel. Applicable only to properties that will be displayed in Persona and UMG. https://unreal-garden.com/docs/uproperty/#neveraspin #UnrealEngine

AlwaysAsPin UPROPERTY(meta=(AlwaysAsPin)) Docs: The property is always exposed as a data pin. Applicable only to properties that will be displayed in Persona and UMG. https://unreal-garden.com/docs/uproperty/#alwaysaspin #UnrealEngine

Interp UPROPERTY(Interp) "Makes a variable animate-able on timelines. Works for any kind of timeline, including in UMG. For a more detailed example (https://benui.ca/unreal/ui-animation/exposing-new-properties-to-animation)." https://unreal-garden.com/docs/uproperty/#interp #UnrealEngine

Untracked UPROPERTY(meta=(Untracked)) Docs: Used for SoftObjectPtr/SoftObjectPath properties to specify a reference should not be tracked. This reference will not be automatically cooked or saved into the asset registry for redirector/delete

AssetRegistrySearchable UPROPERTY(AssetRegistrySearchable) Docs: The `AssetRegistrySearchable` Specifier indicates that this property and its value will be automatically added to the Asset Registry for any Asset class instances containing this as a member variable. It is not legal to use on struct

AllowedTypes UPROPERTY(meta=(AllowedTypes="abc")) "The only time this is actually used is inside the Lyra Example Project but has existed in the engine prior to Unreal Engine 5.0. To confirm that it exists within the engine you can look inside `PrimaryAssetIdCustomization.cpp` and look for

ConfigRestartRequired UPROPERTY(meta=(ConfigRestartRequired=true)) "Used in `config`-marked Project Settings and Editor Preferences variables. When variables marked with this are changed, Unreal prompts the user to restart their editor for the changes to take

ConfigHierarchyEditable UPROPERTY(meta=(ConfigHierarchyEditable)) "In the engine only seems to be used in settings files, and is requires `Config` or `GlobalConfig`." https://unreal-garden.com/docs/uproperty/#confighierarchyeditable #UnrealEngine

GlobalConfig UPROPERTY(GlobalConfig) Docs: Works just like `Config` except that you cannot override it in a subclass. Cannot be given a value in default properties. Implies `BlueprintReadOnly`. https://unreal-garden.com/docs/uproperty/#globalconfig #UnrealEngine