NRF Debug View in VS Code not showing Thread Viewer Reliably

[Dave012]

Hi folks,

I'm using v3.2.2 of the nRF Connect SDK Toolchain, debugging an nRF54LM20-DK board in VS Code.

I've noticed that the "Thread Viewer" under the NRF Debug view does not reliably show up. Sometimes it will show up if I click "Flash", followed by "Debug" (which appears to flash the image a second time). However, if I just I just hit the 'debug' button alone, the "Thread Viewer" doesn't show up.

If the "Thread Viewer" is visible, and I use the 'restart' debug button, the target will restart at main(), but the "Thread Viewer" will disappear. 

I have "Optimize for debugging" set as well as "Include debug thread information". There are no spaces in the path to my project.

Note that my issue is not an empty Thread Viewer as some other folks have commented on, but a totally missing Thread Viewer.

Other folks on my team have similar issues.

Here is a screenshot of the NRF Debug view.

Thoughts?

Dave J.

[Susheel Nuguru]

Have you tried enabling these configs in your prj.conf?

CONFIG_MULTITHREADING
CONFIG_DEBUG_THREAD_INFO
CONFIG_THREAD_MONITOR
CONFIG_THREAD_NAME

[Dave012]

Yes, I have tried enabling these configs in my prj.conf.

Note that the Thread Viewer will start and show me information if I follow these steps:
1. Build the image
2. Flash the image
3. Hit the debug button

If I then hit 'stop' and then hit 'debug' again, the Thread Viewer will not be visible. If it is visible and I hit the 'restart'  button, after the debugger restarts the processor, the Thread Viewer will not be visible.

Thanks,

Dave

[Dave012]

I believe there is a bug present, but I found a workaround: 

In VS Code, Go to File->Preferences->Settings

Search for "Debugging:Flash"

Uncheck the box

When I unset this option, the Thread Viewer appears to always show up when I either start debugging or while debugging if I hit the restart button.

[Susheel Nuguru]

Thanks for lettings us know about that David, it shows that there is most likely a bug in our nrf connect extension in VSC. I will let the team know.

[hotlanta]

Can confirm what Dave012 is seeing and that his work around works. Only happens on some projects (even with the same toolchain) but once it happens, the only way to restore the thread view is his work around.

I am using:

• nrf extension pack: 2025.4.4
• SDK and tool chain on 3.2.4
• Using latest version of MacOS

[Susheel Nuguru]

The nrf connect VS code extension team thinks that this is a race condition in the extension and seems already fixed internally and will be come out in the next release. thanks for bringing this to our attention.