Diagram rendering degradation, June 2026
Severity | Degradation |
|---|---|
Duration | Around 8 hours |
Scope | Diagram rendering only |
#What happened
On 17 June 2026 our diagram rendering service returned a growing number of errors. Affected diagrams showed an error state or appeared blank, and earlier in the window a refresh would often draw them correctly.
Only rendering was affected. Editing, storage and every other part of the product continued to work normally, and no diagram content was lost.
#Timeline (UTC)
Time | Event |
|---|---|
06:30 | Rendering began returning intermittent errors, with most requests still succeeding |
06:30 - 14:30 | The error rate rose steadily through the morning as the capacity shortfall worsened |
14:30 | The error rate peaked, with most diagram requests failing |
15:00 | We identified the cause and applied a fix. Rendering recovered shortly afterwards |
#How you would have known
PlantUML, Mermaid or BPMN diagrams showing an error instead of the drawing
Diagrams appearing blank on a page that was fine the day before
A refresh fixing it, early in the window
#Customer data
No customer data was affected. The diagram source is stored in your own Confluence site and was never touched; only the live rendering of it failed.
#Resolution
Diagrams drew normally again once the fix was applied. No action was needed from customers.
#Related
Written up, kept, and linked from the docs.
