Symptoms

It is required to disable the All Products filter in the search bar in the help center (knowledge base).

Solution

In Settings - Brand Management, specify in CSS Styles

To remove the product selection in the search bar

.helpcenter-search .helpcenter-search-product-filter {
  display: none;
}

To make the left side of the search bar nicely rounded

.helpcenter-search-input {
  border-radius: 8px !important;
}