I use a “reusable block” which defines my line in one place and that appears in all the pages it is used in.
The HTML of the block is
<p class="post-last-modified"><code>[lmt-page-modified-info]</code>. <em>Do visit this page regularly as we will update it to reflect any changes in circumstances.</em></p>
which worked fine until recently. Now the shortcode is empty.
I would dearly like to see a full list of shortcodes and switches for them. In particular is there any difference in [lmt-page-modified-info] and [lmt-post-modified-info]