vastlint
VAST-4.0-tracking-event-removed

VAST-4.0-tracking-event-removed

fullscreen/exitFullscreen tracking events were removed in VAST 4.0

WarningValuesIAB VAST 4.0 §2.4.1VAST 4.0, 4.1, 4.2, and 4.3

Short answer

The fullscreen and exitFullscreen tracking event values were removed in VAST 4.0. Players conforming to 4.0+ will not fire these events. Use playerExpand / playerCollapse instead.

Why this matters in production

This rule is a strong risk signal. Tags with this issue often still parse, but they become brittle across SDKs, SSAI resolvers, and CTV environments. Value-format rules tend to fail at the moment a player interprets a field such as duration, skipoffset, bitrate, or versioning. They are especially painful because the XML can look valid at a glance. Affected scope: VAST 4.0, 4.1, 4.2, and 4.3.

How to fix

Replace fullscreen with playerExpand and exitFullscreen with playerCollapse for VAST 4.0+ compatibility.

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