*   Deprecate `render` locals to be assigned to instance variables.

    *Petrik de Heus*

*   Remove legacy default `media=screen` from `stylesheet_link_tag`.

    *André Luis Leal Cardoso Junior*

*   Change `ActionView::Helpers::FormBuilder#button` to transform `formmethod`
    attributes into `_method="$VERB"` Form Data to enable varied same-form actions:

        <%= form_with model: post, method: :put do %>
          <%= form.button "Update" %>
          <%= form.button "Delete", formmethod: :delete %>
        <% end %>
        <%# => <form action="posts/1">
            =>   <input type="hidden" name="_method" value="put">
            =>   <button type="submit">Update</button>
            =>   <button type="submit" formmethod="post" name="_method" value="delete">Delete</button>
            => </form>
        %>

    *Sean Doyle*

*   Change `ActionView::Helpers::UrlHelper#button_to` to *always* render a
    `<button>` element, regardless of whether or not the content is passed as
    the first argument or as a block.

        <%= button_to "Delete", post_path(@post), method: :delete %>
        <%# => <form action="/posts/1"><input type="hidden" name="_method" value="delete"><button type="submit">Delete</button></form>

        <%= button_to post_path(@post), method: :delete do %>
          Delete
        <% end %>
        <%# => <form action="/posts/1"><input type="hidden" name="_method" value="delete"><button type="submit">Delete</button></form>

    *Sean Doyle*, *Dusan Orlovic*

*   Add `config.action_view.preload_links_header` to allow disabling of
    the `Link` header being added by default when using `stylesheet_link_tag`
    and `javascript_include_tag`.

    *Andrew White*

*   The `translate` helper now resolves `default` values when a `nil` key is
    specified, instead of always returning `nil`.

    *Jonathan Hefner*

*   Add `config.action_view.image_loading` to configure the default value of
    the `image_tag` `:loading` option.

    By setting `config.action_view.image_loading = "lazy"`, an application can opt in to
    lazy loading images sitewide, without changing view code.

    *Jonathan Hefner*

*   `ActionView::Helpers::FormBuilder#id` returns the value
    of the `<form>` element's `id` attribute. With a `method` argument, returns
    the `id` attribute for a form field with that name.

        <%= form_for @post do |f| %>
          <%# ... %>

          <% content_for :sticky_footer do %>
            <%= form.button(form: f.id) %>
          <% end %>
        <% end %>

    *Sean Doyle*

*   `ActionView::Helpers::FormBuilder#field_id` returns the value generated by
    the FormBuilder for the given attribute name.

        <%= form_for @post do |f| %>
          <%= f.label :title %>
          <%= f.text_field :title, aria: { describedby: f.field_id(:title, :error) } %>
          <%= tag.span("is blank", id: f.field_id(:title, :error) %>
        <% end %>

    *Sean Doyle*

*   Add `tag.attributes` to transform a Hash into HTML Attributes, ready to be
    interpolated into ERB.

        <input <%= tag.attributes(type: :text, aria: { label: "Search" }) %> >
        # => <input type="text" aria-label="Search">

    *Sean Doyle*


Please check [6-1-stable](https://github.com/rails/rails/blob/6-1-stable/actionview/CHANGELOG.md) for previous changes.