diff --git a/js/src/modal.js b/js/src/modal.js
index fb787208d8..1ea630c415 100644
--- a/js/src/modal.js
+++ b/js/src/modal.js
@@ -113,7 +113,7 @@ const Modal = (() => {
     }
 
     show(relatedTarget) {
-      if (this._isTransitioning) {
+      if (this._isTransitioning || this._isShown) {
         return
       }
 
diff --git a/js/tests/unit/modal.js b/js/tests/unit/modal.js
index e026cd7f14..e081a6dc25 100644
--- a/js/tests/unit/modal.js
+++ b/js/tests/unit/modal.js
@@ -673,4 +673,20 @@ $(function () {
     $toggleBtn.trigger('click')
     setTimeout(done, 500)
   })
+
+  QUnit.test('should not try to open a modal which is already visible', function (assert) {
+    assert.expect(1)
+    var done = assert.async()
+    var count = 0
+
+    $('<div id="modal-test"/>').on('shown.bs.modal', function () {
+      count++
+    }).on('hidden.bs.modal', function () {
+      assert.strictEqual(count, 1, 'show() runs only once')
+      done()
+    })
+      .bootstrapModal('show')
+      .bootstrapModal('show')
+      .bootstrapModal('hide')
+  })
 })