in responsive layouts <767px, ensure inputs are not larger than 100% with box-sizing and a max-width

docs/assets/css/bootstrap-responsive.css

@@ -168,6 +168,16 @@
     width: auto;
     margin: 0;
   }
+  input,
+  textarea,
+  select,
+  .uneditable-input {
+    -webkit-box-sizing: border-box;
+    -moz-box-sizing: border-box;
+    -ms-box-sizing: border-box;
+    box-sizing: border-box;
+    max-width: 100%;
+  }
 }
 @media (min-width: 768px) and (max-width: 979px) {
   .row {

docs/assets/css/bootstrap.css

@@ -3678,6 +3678,7 @@ a.thumbnail:hover {
   box-shadow: inset 0 -1px 0 rgba(0, 0, 0, 0.15);
   -webkit-box-sizing: border-box;
   -moz-box-sizing: border-box;
+  -ms-box-sizing: border-box;
   box-sizing: border-box;
   -webkit-transition: width 0.6s ease;
   -moz-transition: width 0.6s ease;

less/mixins.less

@@ -252,6 +252,7 @@
 .box-sizing(@boxmodel) {
   -webkit-box-sizing: @boxmodel;
      -moz-box-sizing: @boxmodel;
+      -ms-box-sizing: @boxmodel;
           box-sizing: @boxmodel;
 }
 

less/responsive.less

@@ -188,6 +188,17 @@
     width: auto;
     margin: 0;
   }
+
+  // FORM FIELDS
+  // -----------
+  // Make them behave like divs
+  input,
+  textarea,
+  select,
+  .uneditable-input {
+    .box-sizing(border-box);
+    max-width: 100%;
+  }
 }