How to use alternative RTT viewer tools

In our application firmware, we’re using Segger RTT over SWD (without an SWO pin) for console output.

Following cortex-debug release V0.4.0, we changed our project’s .vscode/launch.json in a branch to utilize the new built-in RTT support (diff pictured below). Now with that change, I can no longer connect to the console output with other tools, such as Segger’s RTT Viewer, or a telnet client on port 19021. How can I get that working again?

I see in the changelog, it says,

It is perfectly fine to have Cortex-Debug enable RTT but not use any display features. This way you can use external tools (like JLink tools or custom ones)

That seems to be referring to what I’m asking, but how do I “not use any display features”? And does that mean I need to edit the launch.json whenever I want to use a different tool?

I tried removing the "decoders" key & value from the "rttConfig" section in launch.json, and was able to connect with Segger RTT Viewer, but not a telnet client (KiTTY on port 19021). Is this what the quote above means? If so, why doesn’t it work with the telnet client?

Is there a way to make it both output to the built-in Terminal, and support support external viewers simultaneously? Or to let me choose between them at runtime (without making config file changes)?

… Currently, the main features that have me wanting to use other viewers are (1) logging to (uniquely named) files, and (2) per-line timestamping. If those were possible with VSCode / Cortex Debug, I would probably just use that, and not care about the external viewers, at least for the time being. But I don’t mind using external viewers to get those features. I just need some way to do it.

Thanks for your work on these tools and features. 😃