FIX: improves positioning of sk in mobile when inside a modal (#9657)

app/assets/javascripts/select-kit/components/select-kit.js

@@ -782,17 +782,30 @@ export default Component.extend(
               enabled: window.innerWidth <= 450,
               phase: "main",
               fn({ state }) {
+                if (!inModal) {
                   let { x } = state.elements.reference.getBoundingClientRect();
                   state.modifiersData.popperOffsets.x = -x + 10;
                 }
+              }
             },
             {
               name: "applySmallScreenMaxWidth",
               enabled: window.innerWidth <= 450,
               phase: "beforeWrite",
               fn({ state }) {
+                if (inModal) {
+                  const innerModal = document.querySelector(
+                    "#discourse-modal div.modal-inner-container"
+                  );
+
+                  if (innerModal) {
+                    state.styles.popper.width = `${innerModal.clientWidth -
+                      20}px`;
+                  }
+                } else {
                   state.styles.popper.width = `${window.innerWidth - 20}px`;
                 }
+              }
             },
             {
               name: "sameWidth",