I presume your system is Linux and you installed LibreWolf as a snaps or flatpak package. When installed like this, the browser isn't aware of your system's proxy settings, you will need to set the localhost and port of proxy manually.
You are right, but is there a way to solve this. Now I'm using foxyproxy in LW for this reason, but it would be better to solve the problem and use the whole system proxy.
Try it with a new profile, so that there are no plugins and only default settings.
It didn't work.
LibreWolf
Welcome to the official community for LibreWolf.
LibreWolf is designed to increase protection against tracking and fingerprinting techniques, while also including a few security improvements. LibreWolf also aims to remove all the telemetry, data collection and annoyances, as well as disabling anti-freedom features like DRM. If you have any question please visit our FAQ first: https://librewolf.net/docs/faq/
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