Function find_editor_block 

pub(super) fn find_editor_block(
    mstore: &Store,
    tab_id: &str,
    connection: &str,
) -> Result<Option<Block>, String>

Find an Editor-view block the tab shows (shown_block_ids: in front of its stack, not minimized, not hidden behind a magnified pane) on connection (its meta connection; absent and local are this computer), if any. Direct sibling of find_agent_block above, checking meta.view == "editor" instead of meta.agentId. An editor on another connection is never it: its reads and saves go there (remote terminals spec §6.3).