Magento 2 Login Popup not firing on Proceed to Checkout

Question

Configuration:

• Magento 2.3.5. p1
• Guest checkout disabled
• Cookie lifetime 604800

Test scenario 1: When I enter the site the user seems to be logged in as it shows the name in the welcome message. After adding 1 product to the cart and pressing Proceed to Checkout the the cart does not proceed to the checkout page and the login popup also does not open.

Test scenario 2 : If I log in and log out, and add a product to cart as guest and press Proceed to Checkout the popup window opens.

How can I troubleshoot on scenario 1 the reason why it neither proceeds to checkout or shows the login popup? The source code for both scenarios does not show any customer information, so it looks that both are in guest mode.

Answer 1

Is your cart cleaned after failing to start checkout? Sometimes errors are not available in the logs. What is returned by proceed to checkout request? Remember to enable developer mode. Do you have any third party modules? Recently I have discovered that one of the GDPR Cookie modules sets cookie expiry date in GMT timezone. When that cookie is not present, other cookies are removed.