Comment by rasz

>slipped past umatrix & ublock origin on my first try. Given that I launched chromium by dragging the link onto its icon the first time, perhaps the script-blocking extensions weren't fully loaded?

Yes. Chrome will actually pause extensions loading to deliver you that first rendered picture fraction(arguable, probably slower in the end considering extensions load from disk) of a second faster. I think it was direct uBO sabotage.

TLDR: First website loaded by starting browser with a link or from last session has almost 100% chance of bypassing uBlockOrigin. Chrome and Chromium based browsers are not User Agents, they are Google Agents.