The Rust and web related extensions work pretty well. I've been using that for a while.
There are a few more around.
I would like to see some analysis of the telemetry Jetbrains sends and whether you can turn it off. It's a paid pro IDE so it wouldn't surprise me if you can really disable it because some commercial customers will not want telemetry. In high security environments it's often considered bad due to the possibility of accidentally exposing secret information.
Use your operating system's firewall app to block all outbound connections from it.
I wasn't aware I could configure firewall rules for specific applications. Any hints where I could start looking at that?
Source for this? Does VSCodium with no extensions send telemetry, or is it the extension issue?
EDIT: Oh the quote from VSCodium is in the article:
Even though we do not pass the telemetry build flags (and go out of our way to cripple the baked-in telemetry), Microsoft will still track usage by default.
The funny thing is that I was about to install VSCodium for the first time TODAY, because I want live markdown preview. (I want a doc editor, not necessarily a code editor)
The rationale for VSCodium says it's about telemetry, although strictly speaking it's doesn't promise they removed all the telemetry!
but the product available for download (Visual Studio Code) is licensed under this not-FLOSS license and contains telemetry/tracking
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I should also say that on the dev side, crash reports are EXTREMELY useful and really do improve the quality of the software. But you used to have to confirm this data would be sent.
After reading, this seems impossible, short of going down to DNS or network blocks of some kind: the "disable telemetry" setting doesn't; extensions have their own telemetry; MS consider the data sufficiently anonymous to be exempt from GDPR, even the vscodium maintainers say they found it impossible to block vs code's eager telemetrizing.
I wonder what is the most effective way of actually completely stopping it phoning home, apart from yanking its ethernet cable?