What changed
Google's Antigravity App 2.28.0 adds an in-session browser, PDF viewer, arbitrary-file attachments and finer diff highlighting. The 2.28.1 follow-up adds turn-by-turn conversation navigation plus third-party-tool notices and plugin developer, version, website and repository details.
Why it matters
The release keeps more web and document work inside an agent session while making plugin origin easier to inspect. That reduces context switching and improves provenance cues, but it also expands the untrusted-content, upload, rendering and third-party-tool surface beside agent permissions.
What to do
Canary 2.28 with benign and adversarial pages, a large PDF, synthetic unknown file types and one third-party plugin. Verify upload limits, renderer isolation, prompt-injection handling, diff fidelity, plugin identity and repository links, effective permissions and revocation before allowing sensitive workspaces.
Caveat
Google's dated changelog establishes the gradual rollout and interface changes. Notices and developer links do not verify a plugin, constrain its permissions or prove safe data handling; malware scanning, renderer isolation, prompt-injection resistance and retention behavior were not independently tested.