 by <code>extensions.objectFormat</code>), or
<em>sha1</em> if no value is set or outside a repository..</p>
<div class="paragraph">
<p>Note: At present, there is no interoperability between SHA-256
repositories and SHA-1 repositories.</p>
</div>
</dd>
</dl>
</div>
<div class="paragraph">
<p>Historically, we warned that SHA-256 repositories may later need
backward incompatible changes when we introduce such interoperability
features. Today, we only expect compatible changes. Furthermore, if such
changes pro