# Devin: model degradation notifications, lightbox improvements, MCP marketplace entry

> Devin Ultra now alerts on lead model degradation/recovery. Several UX refinements: image lightboxes show captions and navigation, attachment previews offer copy-link and copy-content, PR diffs are virtualised for faster session switching, and the preview tab is renamed to Browser. A new MCP entry (Cello) is in the marketplace. Automation schedules can store timezones. Slack muting moves the session to the webapp.

| | |
|---|---|
| **Tool** | Devin |
| **Version** | — |
| **Kind** | release |
| **Published** | 2026-08-19 |
| **Observed** | 2026-08-21 |
| **Significance** | 2/5 |
| **Breaking** | no |
| **Categories** | feature, capability |

## What changed


- **Model degradation**: Ultra sessions notify on lead action model degradation and recovery.
- **Lightbox**: filename captions, image counter, prev/next arrows; review comment images open in lightbox.
- **Attachment previews**: copy link and copy content actions.
- **PR tab**: diff files virtualised for faster session switching.
- **CI failures**: worklog "CI failed" rows open PR review tab with checks expanded.
- **Preview tab renamed** to "Browser".
- **Slack mute**: disconnects from the Slack thread, continues in the webapp.
- **Automation schedules**: timezone storage for schedule triggers.
- **Code scan**: filter by scan mode (discover/ingest).
- **User metrics CSV**: includes Group(s) column.
- **Git provider settings**: connection detail sheet with management actions.
- **MCP marketplace**: Cello MCP added.


## Sources

- [page_diff](https://docs.devin.ai/release-notes/overview#august-19-2026) — retrieved 2026-08-21


## Community

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and never blended._

---
Canonical: https://changelogs.info/devin/devin-model-degradation-notifications-lightbox-improvements-mcp-marketplace-entr
Entity: https://changelogs.info/devin
Event ID: `evt_2026-08-19_devin_august-19-2026`
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