src/vs/platform/remote/common/tunnel.ts/AbstractTunnelService/getTunnelFromMap
class AbstractTunnelService:	protected getTunnelFromMap(remoteHost: string, remotePort: number): { refcount: number, readonly value: Promise<RemoteTunnel | undefined> } | undefined {
		let hosts = [remoteHost];
		// Order matters. We want the original host to be first.
		if (isLocalhost(remoteHost)) {
			hosts.push(...LOCALHOST_ADDRESSES);
			// For localhost, we add the all interfaces hosts because if the tunnel is already available at all interfaces,
			// then of course it is available at localhost.
			hosts.push(...ALL_INTERFACES_ADDRESSES);
		} else if (isAllInterfaces(remoteHost)) {
			hosts.push(...ALL_INTERFACES_ADDRESSES);
		}

		const existingPortMaps = hosts.map(host => this._tunnels.get(host));
		for (const map of existingPortMaps) {
			const existingTunnel = map?.get(remotePort);
			if (existingTunnel) {
				return existingTunnel;
			}
		}
		return undefined;
	}