I know httpOnly cookies are designed to only be altered by the server, however is it possible to delete/overwrite an httpOnly cookie from JavaScript?

My use case is to support logout functionality from the client, even when the server is unavailable due to connectivity issues.

Currently if the server is inaccessible, the authentication cookies remain behind because the server is required to clear them.

An alternative I was thinking of was setting an "offline-logout=true" cookie from the client that the server can detect on the next request and act accordingly.