Add a config option to disable telemetry

[nickjj]

Description of the new feature/enhancement

Going by the source code located at https://github.com/microsoft/terminal/blob/master/src/terminal/parser/telemetry.cpp it seems like maybe the terminal is logging all sorts of data as part of its telemetry system and then sending it back to Microsoft.

Like VSCode, it would be nice to be able to opt out of this by disabling telemetry in the settings.

Proposed technical implementation details (optional)

Expose an option in the config to allow disabling it.

Going by https://github.com/microsoft/terminal/blob/master/doc/cascadia/SettingsSchema.md there doesn't seem to be an option for this.

It would also be nice if someone can reply back here with more details on what exactly is tracked and how it's sent to Microsoft as of today and if that'll change in v1.0's release.

[DHowett-MSFT]

Couple points:

1. We aren’t hiding anything, and you can find details about everything that’s going into a trace logging stream in our source code. The keyword you’ll want to look for is TraceLoggingWrite.
2. The event stream you’ve identified is local-only. Using the .wprp file in our source folder (it’s just XML, you can also crack it open if you want) coupled with the Windows Performance Analyzer, you can capture and evaluate these tracing events. They’re only active when WPR/WPA is listening, which is by explicit user action, and none of the information generated leaves your machine.

We call this system ETL, and I have to admit I’m not sure what it stands for. Its primary use is local opt-in diagnostics, and any diagnostic data generated using it doesn’t leave the machine.

In the Terminal source subtree (src/cascadia), you’ll find some trace loggers that are annotated with additional flags (something something MEASURES). Those are also for local diagnostics, but they can be sampled if, and only if, your Windows diagnostic information configuration allows it.

To date, we’ve used those to determine...

• what level of padding to apply by default (8)
• that we should bind Ctrl+c/v by default
• that Terminal is able to start up CMD in less than a tenth of a second
• nothing else.

Hope that gives you a bit more information. Since these are either entirely local event streams or configured by your global Windows opt-out, I’m gonna close this one out as Question/Answered.

[DHowett-MSFT]

(Let me know if I can shine any more light for you!)

[nickjj]

Thanks for the speedy reply.

So for clarity, no matter what your Windows settings are, there is never a single byte of information that is sent back to Microsoft when it comes to opening the terminal and either typing into it or opening files?

Also, what is the "global Windows opt-out" feature you mentioned? I was under the impression it's not possible to opt out of basic telemetry -- at least not on the home / pro versions of Windows.

[kilasuit]

@DHowett please re-open and either give us a configuration setting (in our Terminal profiles) that allows us to individually consent/remove consent to providing telemetry or agree that you'd accept a PR with this setting in if one was submitted

[DHowett]

If somebody were to contribute this, we'd evaluate it for inclusion. I'm not certain why the Windows global collection setting is insufficient, but I trust the community has a reason for believing that it isn't.

[nickjj]

I'm not certain why the Windows global collection setting is insufficient

Can you go into more detail on how this works? I asked a follow up question on this in a previous reply but I'm still not clear on how that can be modified to not collect or send out anything as a regular person using the Pro version of Windows.

VSCode has an explicit telemetry option, which is also a Microsoft product so it seems reasonable that this terminal could at least think about adding the feature too.

but I trust the community has a reason for believing that it isn't

I can't speak for the whole community but I know my line of thinking was "VSCode has an option to disable this but the Terminal doesn't while having code related to telemetry, so it must be collecting and sending a bunch of potentially identifiable stats to Microsoft". Most folks don't have the knowledge to crawl through the entire code base line by line to see what the telemetry bits really do and then remember to repeat this step every time the code base changes.

I'm with @kilasuit here. If you're open to accepting pull requests on this, should this be re-opened? Someone who is fishing through issues to contribute to the project may never see your request for maybe including it if it's closed.

[kilasuit]

I'm not certain why the Windows global collection setting is insufficient, but I trust the community has a reason for believing that it isn't.

It's just because sometimes you just don't want any telemetry being shared at all, something that PowerShell and dotnet have accepted and have options for fully disabling telemetry in their products

[DHowett]

I'm not arguing that part -- it's just that PowerShell and dotnet don't use the system tracelogging edifice that's controlled by the OS. Because this is an OS-derived project, it does. That's why I'm confused... is it something we could make clearer in our docs?

(@nickjj - I owe you a more detailed response, but I'm working on the shorter easier ones first 😕)