#44449: `contextPerRenderKey` doc

docs/sources/image-rendering/draft_context_per_render_key.md

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+title = "DRAFT"
+description = "DRAFT"
+keywords = ["grafana", "image", "rendering", "plugin"]
+draft = true
++++
+
+[//]: # 'TODO: put it below https://github.com/grafana/grafana/blob/e904f423e4f8caf495c285e4fc28fbcc44638048/docs/sources/image-rendering/_index.md#L77'
+
+#### Context per render key
+
+In `contextPerRenderKey` mode, the plugin will reuse the
+same [browser context](https://chromedevtools.github.io/devtools-protocol/tot/Target/#method-createBrowserContext) for
+all rendering requests sharing the same `renderKey` auth cookie and target domain within a short time window. Each new
+request will open a new page within the existing context. Contexts are closed automatically after 5s of inactivity.
+
+In the case of `contextPerRenderKey` mode, the `clustering.max_concurrency` option refers to the number of open contexts
+rather than the number of open pages. There is no limit to the latter.
+
+`contextPerRenderKey` was designed to improve the performance of the [dashboard previews crawler](TODO: ADD LINK).