As announced in the July release, we are introducing a new debugging experience for VS Code to replace Cortex-Debug. The new debugger has been named "nRF Debug" and is based on Microsoft's debug adapter. nRF Debug is bundled with the extension and offers a custom made debugging experience for the nRF Connect SDK.
In this release, we switched the default setting for the debugger backend to nRF Debug, as we believe it offers a better debugging experience for most users. We added features to nRF Debug that are typically found in other embedded systems' debuggers, and worked on improving its stability and performance throughout.
Generally, all features from Cortex-Debug are available in nRF Debug, but they are located and behave differently. The debug console now outputs the GDB output in addition to output from the J-Link GDB Server, which no longer opens in a dedicated terminal window. GDB Commands can be passed to the debugger in the debug console by prefixing them with -exec. For instance, the command -exec info threads shows GDB's thread list.
The program execution commands, such as continue, are not supported in the debug console for now as they bypass the debug adapter, thus desynchronizing VS Code from GDB.