TensorList operations.
    *   `tf.custom_gradient` can now be applied to functions that accept nested
        structures of `tensors` as inputs (instead of just a list of tensors).
        Note that Python structures such as tuples and lists now won't be
        treated as tensors, so if you still want them to be treated that way,
        you need to wrap them with `tf.convert_to_tensor`.

pointer-events: none;\n    background-color: transparent;\n    // Remove CSS gradients if they're enabled\n    @if $enable-gradients {\n      background-image: none;\n    }\n  }\n}\n\n.dropdown-menu.show {\n  display: block;\n}\n\n// Dropdown section headers\n.dropdown-header {\n  display: block;\n  padding: $dropdown-padding-y $dropdown-item-padding-x;\n  margin-bottom: 0; // for use with heading elements\n  @include font-size($font-size-sm);\n  color: $dropdown-header-color;\n  white-space: nowrap;...

pointer-events: none;\n    background-color: transparent;\n    // Remove CSS gradients if they're enabled\n    @if $enable-gradients {\n      background-image: none;\n    }\n  }\n}\n\n.dropdown-menu.show {\n  display: block;\n}\n\n// Dropdown section headers\n.dropdown-header {\n  display: block;\n  padding: $dropdown-header-padding;\n  margin-bottom: 0; // for use with heading elements\n  @include font-size($font-size-sm);\n  color: $dropdown-header-color;\n  white-space: nowrap; // as with > li > a\n}\n\n//...