How do I create a button in the classic Sales UI using Application Composer?

You can create a button as an action or link using Application Composer. Keep in mind that you must use a sandbox for your configuration and verify the changes before publishing your sandbox.

Here's how you can create and add a button to a page in Classic UI:

Create a button

1. Go to Tools > Application Composer, and select the application you wish to configure.
2. Expand the object where you want to add the button, and then select Actions and Links.

3. In the details region, specify the properties of the button you want to add. For example:

   1. Select Action to run a script, or Link to enter a URL.
   2. For Action, open the Groovy script editor and write the logic for your button.
   3. For Link, enter the static URL in double quotation marks or use the expression builder to create a dynamic URL based on object fields.

After saving the Action or Link, now you must add the button to the relevant page layout of the object to make the button available to the users.

Add the button

1. Go to Tools > Application Composer, and expand the object where you want to add the button
2. Select Pages, and then select the layout to which you want to add the button.
3. Edit the layout to add the button you've created.