Bug: Single checkout for multiple levels fails if the Stripe transaction requires SCA

[dwanjuki]

Describe the bug
When checking out for multiple levels in one go and if 3D Secure Authentication is required for the Stripe transactions (for example if Stripe Radar is enabled), only the first membership level payment is processed. A blank page is displayed and only the first membership level is assigned.

To Reproduce
Steps to reproduce the behavior:

1. Create some membership levels and set Stripe as payment gateway.
2. On the levels page, select more than one membership level.
3. At checkout use card details that will trigger SCA, such as these test cards for sandbox accounts, or other valid card details if Radar is enabled
4. See bug

Expected behavior
Payment is collected for all selected membership levels and all the membership levels are assigned to the user.

Isolating the problem (mark completed items with an [x]):

• I have deactivated other plugins and confirmed this bug occurs when only Paid Memberships Pro plugin is active.
• This bug happens with a default WordPress theme active, or Memberlite.
• I can reproduce this bug consistently using the steps above.

WordPress Environment

WP 6.2 PHP 8.0.28 PMPro 2.10.3 MMPU 0.8.3