How To Check Whether User is In Console or Not in Lightning Experience

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:

<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!..

Lightning Web Components (lwc) Are Not Showing in SF While Adding To Layout

Even after pushing the lighting web components into sf ,if it's showing in components list but not showing while adding to any layout ,it means your .js-meta.xml file has some issue.

Please check whether <targets> is specified for this component or not.Targets is nothing but where are in places this component can be accessible/usable like App page ,Record detail page or in home page layout.

Proper js-meta.xml will be like

<?xml version="1.0" encoding="UTF-8"?>
<LightningComponentBundle xmlns="http://soap.sforce.com/2006/04/metadata" fqn="SalesforceSampleLWC">
<apiVersion>46.0</apiVersion>
<isExposed>true</isExposed>
<targets>
<target>lightning__AppPage</target>
<target>lightning__RecordPage</target>
<target>lightning__HomePage</target>
</targets>
</LightningComponentBundle>

Hope this helps you...Enjoy!