Playbook: Deploy a sticky anchor without UX backlash

Playbook: Deploy a sticky anchor without UX backlash
What it does: pins a unit to the screen edge — top viewability, persistent impression.

Setup (effort 2/5):
— Mobile bottom anchor only. Top anchors on mobile trigger CLS and intrusive-interstitial penalties.
— Desktop: a left/right rail sticky beats a bottom bar for CPM.
— Reserve the height in CSS BEFORE render — min-height: 50px on the container. No layout shift.
— Always ship a close (X) button. Google's Better Ads Standards require it; missing it can drop fill.
— Don't stack sticky + anchor + interstitial. Pick one persistent format.

RPM lift seen: +10-18%, almost entirely from the anchor's high viewability.

Pros: best viewability-per-slot of any format. Cons: annoyance if oversized, CLS if unreserved.

Lift: ★★★★☆ — Risk: ★★☆☆☆
Best for: mobile-heavy traffic. Skip if you already run an interstitial.