Magento 2 add custom footer

default.xml from module Magento\Theme add this code inside footer referenceContainer

<block class="Magento\Cms\Block\Block" name="block-footer" after="footer_links">
      <arguments>
            <argument name="block_id" xsi:type="string">block_footer_custom</argument>
      </arguments>

</block>


Goto backend Content > Blocks > Add new static block with identifier name block_footer_custom with any html code you need. It so easy to editable Clear cache and re-

deploy static. Now you will get your custom block