# Readme | Subsystem | Change Type | Change Description | | :------------- | ------------ | ------------------------------------------------------------ | | Common | Verification enhanced | [Permission verification enhanced for system APIs. Now only system applications are allowed to use system APIs. If third-party applications use a system API, error 202 is returned.](changelogs-common.md)| | Ability framework | Behavior changed | [In the **appRecovery** API, the enum names of **RestartFlag** are changed from **NO_RESTART** upon a specific fault to **RESTART** upon a specific fault.](changelogs-ability.md)| | Multi-language runtime subsystem| Parsing rule changed| [LLVM parsing format changed. When your code depends on the **version-script** or **-gcc-toolchain** option, parsing may fail if you continue to use the original LLVM 12 configuration file or options.](changelogs-arkcompiler.md)| | Multi-language runtime subsystem| Verification enhanced | [New alarms are added and existing alarms are enhanced along with the upgrade from LLVM 12 to LLVM 15](changelogs-arkcompiler.md)| | Multi-language runtime subsystem| Verification enhanced | [LLVM emu-tls is changed. If you use both LLVM 12 and LLVM 15, the emu-tls symbol cannot be found in libc++.so.](changelogs-arkcompiler.md)| | Multi-language runtime subsystem| Verification enhanced | [New features and internal interface changes in the official release of LLVM 15 are inherited.](changelogs-arkcompiler.md)| | ArkUI | Behavior changed | [The stack layout issue is fixed.](changelogs-arkui.md) | | ArkUI | Default value changed | [The default state of the scrollbar in the \ and \ components is changed.](changelogs-arkui.md) | | ArkUI | UX changed | [The hover effect of the \