Making the Order Summary Collapsible on the checkout page helps in the small screens of mobile phones.
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Here's how you can enable it for your checkout page using Elementor:
Step 1: Edit your checkout page
Click on 'Edit Elementor Template' to edit your checkout page with Elementor.
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Step 2: Edit the Checkout Form widget
Click on the pencil icon of the Checkout Form widget.
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Step 3: Go to the Sections tab and select the 'Collapsible Order Summary' option
Here you'll find the option to enable the collapsible order summary.
Simply hit the toggle to enable it.
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You can also set the collapsed/expanded view text from here.
Also, you can choose to enable the coupon field and make it collapsible. Plus, you can even turn it into a mini cart by enabling a quantity switcher and allowing product deletion.
Click on Update to save all the changes you made.
There you go! You've now made the order summary collapsible on your checkout page.