diff --git a/js/src/splide.load.js b/js/src/splide.load.js
--- a/js/src/splide.load.js
+++ b/js/src/splide.load.js
@@ -54,8 +54,8 @@
     var d = $.attr(elm, P_DATA + ID);
     var s = $.parse(d);
     var o = $.extend({}, CONFIG.defaults || {}, s);
-    var r = o.breakpoints;
-    var x = CONFIG.extras || {};
+    var r = o.breakpoints ? $.extend({}, o.breakpoints) : null;
+    var x = $.extend({}, CONFIG.extras || {});
     var p = elm.parentNode;
     var unSplide = $.hasClass(elm, 'unsplide');
     var instance;
@@ -66,14 +66,15 @@
     // Basically a soft destroy if one slide: disable arrows, pagination, etc.
     if (o.count && o.count === 1) {
       resets = CONFIG.resets || {};
-      x = $.extend(x, resets);
-      o = $.extend(o, resets);
+      x = $.extend({}, x, resets);
+      o = $.extend({}, o, resets);
     }
 
     // Still required by v4, else destroy bubbles up to the closest breakpoint.
     // This basically feeds each breakpoints with default values, a legacy
     // Slick approach which do not feed breakpoints with their defaults.
     if (r) {
+      o.breakpoints = r;
       for (b in r) {
         if ($.hasProp(r, b)) {
           var breakpoint = r[b];
diff --git a/js/splide.load.min.js b/js/splide.load.min.js
--- a/js/splide.load.min.js
+++ b/js/splide.load.min.js
@@ -1 +1 @@
-!function(u,t,e,p,c,f){"use strict";var h="splide",i=h,m="is-mounted",v="data-",a="."+h+"--default:not(."+m+", ."+h+"--vanilla)",x=e.splide||{};p=u.extend(p||{},{init:function(t){return t.splide||(t.splide=function(n){var t,e,i=u.attr(n,v+h),a=u.parse(i),r=u.extend({},x.defaults||{},a),s=r.breakpoints,o=x.extras||{},d=n.parentNode,i=u.hasClass(n,"unsplide");r.count&&1===r.count&&(a=x.resets||{},o=u.extend(o,a),r=u.extend(r,a));if(s)for(e in s){var l;u.hasProp(s,e)&&((l=s[e]).destroy||(s[e]=u.extend({},o,l)))}(function(){var t,e;r.randomize&&(e=u.find(n,"."+h+"__list"),u.isElm(e)&&e.children&&(!(t=e.children.length)||0<=(e=Math.floor(Math.random()*t))&&e<t&&(r.start=e)))})(),t=new Splide(n,r),p.initExtensions(),p.initListeners(t),u.hasClass(d,h+"-wrapper")||(d=r.animation||r.type?p.getTransition(r.animation||r.type):null,t.mount(p.extensions||{},d));u.on(n,"click","."+h+"__arrow--down",function(t){t.preventDefault();var e=u.attr(t.target,v+"target"),e=e?u.find(f,e):null,t=u.toInt(u.attr(t.target,v+"offset"),80);u.isElm(e)&&(e=u.rect(e),c.scroll({top:e.top-t,behavior:"smooth"}))}),i&&t.destroy(!0);return u.addClass(n,m),t}(t)),t.splide}}),t.behaviors.splide={attach:function(t){u.once(p.init,i,a,t)},detach:function(t,e,n){"unload"===n&&u.once.removeSafely(i,a,t)}}}(dBlazy,Drupal,drupalSettings,dSplide,this,this.document);
+!function(u,t,e,p,c,f){"use strict";var h="splide",i=h,m="is-mounted",v="data-",a="."+h+"--default:not(."+m+", ."+h+"--vanilla)",x=e.splide||{};p=u.extend(p||{},{init:function(t){return t.splide||(t.splide=function(n){var t,e,i=u.attr(n,v+h),a=u.parse(i),r=u.extend({},x.defaults||{},a),s=r.breakpoints?u.extend({},r.breakpoints):null,o=u.extend({},x.extras||{}),d=n.parentNode,i=u.hasClass(n,"unsplide");r.count&&1===r.count&&(a=x.resets||{},o=u.extend({},o,a),r=u.extend({},r,a));if(s){r.breakpoints=s;for(e in s){var l;u.hasProp(s,e)&&((l=s[e]).destroy||(s[e]=u.extend({},o,l)))}}(function(){var t,e;r.randomize&&(e=u.find(n,"."+h+"__list"),u.isElm(e)&&e.children&&(!(t=e.children.length)||0<=(e=Math.floor(Math.random()*t))&&e<t&&(r.start=e)))})(),t=new Splide(n,r),p.initExtensions(),p.initListeners(t),u.hasClass(d,h+"-wrapper")||(d=r.animation||r.type?p.getTransition(r.animation||r.type):null,t.mount(p.extensions||{},d));u.on(n,"click","."+h+"__arrow--down",function(t){t.preventDefault();var e=u.attr(t.target,v+"target"),e=e?u.find(f,e):null,t=u.toInt(u.attr(t.target,v+"offset"),80);u.isElm(e)&&(e=u.rect(e),c.scroll({top:e.top-t,behavior:"smooth"}))}),i&&t.destroy(!0);return u.addClass(n,m),t}(t)),t.splide}}),t.behaviors.splide={attach:function(t){u.once(p.init,i,a,t)},detach:function(t,e,n){"unload"===n&&u.once.removeSafely(i,a,t)}}}(dBlazy,Drupal,drupalSettings,dSplide,this,this.document);