I built a browser extension called Silenzio that blurs or blacks out videos and images, mutes audio, and lets me set rules about where and when it applies. The motivation is a bit personal: scrolling feeds, search results, and "people you may know" lists kept stealing minutes I didn't actually want to spend. A blurred feed turns out to be a surprisingly effective speed bump. The technically interesting part is that the whole thing — Chrome, Edge, and Firefox — runs from a single source folder. No build step, no per-browser variants, no Webpack. Here's how that works, plus a handful of MV3-specific tricks I had to find along the way. What it does Two independent toggles — videos and images — each with Off / Blur / Blackout. Audio follows the video toggle. Three more knobs on top: an allowlist or blocklist of sites, per-site or global pause timers, and an optional "working hours" schedule so the whole thing only runs during a daily window you pick.…