I am using the openPrimaryTab() method to open a custom page as tab.
<script src="/support/console/43.0/integration.js" />
<script type="text/javascript">
function OpenPrimaryTab() {
//Open a new primary tab with the appropriate case in it
sforce.console.openPrimaryTab(null, 'http://www.salesforce.com', false, 'salesforce', openSuccess, 'salesforceTab');
}
var openSuccess = function openSuccess(result) {
//Report whether opening the new tab was successful
if (result.success == true) {
alert('Primary tab successfully opened');
} else {
alert('Primary tab cannot be opened');
}
};
</script>
Its working in Console Navigation in Salesforce lightning view. But its not working in Standard Navigation in Salesforce lightning view.