The matter.js-based Matter Server, which Home Assistant's Matter integration talks to, reached version 1.5.5 on 24 October 2026. It is the third release in two days, after 1.5.3 and 1.5.4 on 23 October. The main fix is for systems where, after an upgrade to the 1.5 series, only part of the Matter devices came back after a restart.
One damaged node blocked the rest
The bug was reported on 23 October by a user with 47 Thread and Wi-Fi nodes migrated from the old Python Matter Server, running the Matter Server app 9.2.0 with its beta option, which installs the newest server on every start. After a restart picked up version 1.5.0, only 19 of the 47 nodes reached Home Assistant, and 1.5.3 behaved the same.
The cause, as described in the fix (#1214), goes back to older matter.js versions. From 0.15.4 to 0.16.10, every load and save multiplied a node's stored commissioning time-to-live (TTL) by 1000. After about 100 such cycles the value overflowed and was saved as null. matter.js 0.17 did not check that field, so nothing happened. Version 0.18, used since Matter Server 1.5.0, validates it, so the node failed to load. Because the lookup of the other devices stopped at that node, every node stored after it failed to start too.
What 1.5.5 changes
Before the controller starts, the server removes the damaged values from the stored nodes. The commissioning TTL is always dropped, because it is out of date after a restart anyway, and address TTLs only when they are null or out of range. Each node is repaired separately, so one unreadable node does not stop the rest. The first start after the update logs how many nodes were repaired. The developers call this a stopgap until the server moves to a matter.js version that repairs these values on load.
Version 1.5.5 also renames the Aqara LED strip custom cluster from AqaraLedStripT2Cluster to AqaraLedStripCluster, because other Aqara LED devices expose the same cluster.
1.5.3 and 1.5.4: faster startup
Both releases from 23 October shorten the time it takes to set up nodes at startup. Attribute values are converted much faster, and building a node's attribute data no longer pauses after each endpoint. In the developers' measurement on a copy of a 45-node setup, building all snapshots dropped from 575 ms to 19 ms.
Version 1.5.3 also stops dropping events about added and removed nodes and endpoints when a client reads them too slowly. Such a client is now disconnected and gets the current state when it reconnects. The dashboard can now edit thermostat presets, and the server knows the vendor clusters of the Yeelight Cube Lite.
The Home Assistant app
The source of the Matter Server app has moved from the add-ons repository to a new home-assistant/app-matter-server repository, where it was switched to server 1.5.4 on 24 October. The last stable app version, 9.2.0, still bundles server 1.4.0.