https://help.vivaldi.com/desktop/privacy/is-vivaldi-open-sou...
Someone mirrored it.
I don't trust them one bit. There was that telemetry analysis that showed Vivaldi as a very noisy browser.
how so? how do you know this?
You can try building the (supposedly) open-source apps you use from source.
Everyone opining here should MitM themselves every now and then. If not for your own security then maybe to make sure you're not participating in psyop when opining online and resharing hearsay or old truisms.