Ion-slides in modal problem with Safari

On Ionic-Angular, I have a problem with Ion-slides used in a modal and only on Safari.

When launching programmatically, in a modal, my component containing a slider, it opens properly and after a fraction of a second it moves by half the size of the modal and stays between two slides.
If I swipe manually to the last slide, eventually Safari manages to display it correctly.

Example here:
Select a product and click on “Réserver” to open the modal.

I tried the *ngIf and the slides.update() as recommended by others, but nothing worked for me.
Chrome, Firefox and mobile apps are ok.