Loop is not working correctly with coverflow effect

[sanducata]

Check that this is really a bug

• I confirm

Reproduction link

https://codepen.io/sodelll/pen/vELGrJL

Bug description

Loop is not working correctly with coverflow effect. At some point while sliding, no more cards are displayed. It looks like the loop ends after the fifth slide.
I have enabled slideToClickedSlide property, but this is also reproducible with mouse drag. I also tried using loopAdditionalSlides, but it did not work, only made things worse for a dynamic number of slides. I want to have it working for any number of slides, not for just 5.

Note:
This is also reproducible on the carousel-slider plugin while using long mouse drags.

Expected Behavior

Swiper should loop endlessly, it should never reach an end.

Actual Behavior

Looks like the loop ends after the 5th slide (in this case), though dragging or clicking on slide will display the additional slides that were not displayed previously:

Video_2025_09_29-1.webm

Swiper version

12.0.2

Platform/Target and Browser Versions

Windows, Chrome

Validations

• Follow our Code of Conduct
• Read the docs.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.
• Make sure this is a Swiper issue and not a framework-specific issue

Would you like to open a PR for this bug?

• I'm willing to open a PR