Basically if you want to check whether user in Lightning experience console(sales/service consoles in lightning experience not the just lightning experience ) you can use the same sforce console methods which you have used in classic.This method will support in lightning experience with out any changes.
Sample code:
Note:
Even after using this if it's not working please check you version of /support/api/42.0/integration.js. If your version is below 42 then it will not work.So,please change the version it will work automatically.
Hope this helped you..Enjoy!..
Sample code:
<apex:page> <apex:includeScript value="/support/console/42.0/integration.js" /> <apex:includeScript value="/support/api/41.0/interaction.js"/> <button onclick="openTab();" > Console openPrimaryTab</button> <script> function inConsole() { if (sforce.console.isInConsole()) { alert('In console'); }else { alert('Not in console'); } } </apex:page>
Note:
Even after using this if it's not working please check you version of /support/api/42.0/integration.js. If your version is below 42 then it will not work.So,please change the version it will work automatically.
Hope this helped you..Enjoy!..