Yep, inxi please.
Part of the problems are likely related to anti-fingerprinting settings, check if there’s a popup or a little icon left of the address bar to give consent to canvas, also there is an about:config setting privacy.resistFingerprinting.exemptedDomains.
YouTube slowness may have to do with GPU acceleration, check in about:support for “Blocklisted” / “Cannot be enabled in release or beta” (under the “Graphics” section).