rerun --asset
rerun rec.rrd --asset asset.rrd registers the asset with the recording's dataset in the Viewer catalog, so the asset shows up in the recording.
Before this, an asset file written under its own recording id opened as a separate recording.
Every --asset is registered with all datasets that the specified local .rrd recordings end up in, regardless of argument order.
For example, rerun --asset mesh.rrd rec0.rrd rec1.rrd --asset robot.rrd registers both assets with each recording's dataset.
URLs, blueprints, and other non-recording arguments do not receive assets.
Passing --asset without any local .rrd recording produces an error.
--asset can be passed several times and needs Load files via Viewer catalog under Settings → Viewer catalog to be enabled, so it automatically enables the setting if it is off.
See assets for what an asset is, and the CLI manual for the full list of arguments.