Imagine a scenario: You've replaced your URL Hacked buttons with new object-specific actions and dragged them into the Salesforce Mobile and Lightning Experience Actions section part of the Page Layout. You click save, check the object and... your action isn't there? What gives?

The issue is that Quick Actions in the Salesforce Mobile and Lightning Experience Actions simply show in the Chatter tab when Feed Tracking is enabled. It's not made very clear in the help text so many people are finding themselves confused if they haven't actually thought to check Chatter The help text on the Page Layout properties is as follows:
Feed tracking is disabled for this object, but you can still customize actions for Lightning Experience and the mobile app action bar. Actions in this section appear only in Lightning Experience and the mobile app, and may appear in third party apps that use this page layout.

Only after you've disabled Feed Tracking for the object will your actions display at the top of the object details as expected. So let's go ahead and disabled that so our actions show up where users would expect them.

Disable Feed Tracking:

1. Navigate to Setup and search "Feed Tracking"
2. Select the object you'd like to stop tracking from the list on the left
3. Uncheck the "Enable Feed Tracking" checkbox

Navigate back to a record on your object detail page and confirm that your actions now show as expected. If you don't see them, double check the Page Layout and whether you placed the correct action in Salesforce Mobile and Lightning Experience Actions and that you don't already have too many actions selected for the section.

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