I rarely say this but may be worth ensuring you have a good backup/rollback plan and checking raised issues on your important custom integrations before upgrading to #HomeAssistant 2026.2
A change to the way entity_id's are validated is breaking some custom integrations, resulting in missing entities. I fixed my integrations during the beta week but quite a few did not.
This search shows the issue though there may be more if people haven't included the log text.