For anybody using the very handy Collapse-o-matic plugin on WordPress, according to a (slightly vague, and difficult to find) support post, it’s being retired due to ongoing security issues.
The plugin provides an expandable section in blog posts.
Fortunately WordPress now supports this natively via the Display block type. Some people are hunting around for other plugins with additional functionality, but Display looks good to me.
One issue I had was finding which blog posts used Collapse-o-matic.
The solution I found was in the WordPress admin posts page, search for [expand
Then it’s hopefully easy enough to move the relevant content into a Display block, and deactivate the plugin.
For anybody else using WordPress, this is probably a nice reminder to review WP plugins and check for any other vulnerabilities that haven’t been widely advertised.
I was concerned by the vulnerabilities in collapse-o-matic but loved the functionality. I therefore created a new plugin (without the vulnerabilities) that is completely free, not upsells etc. You can find it on the repository under ‘Collapse Magic’ (https://wordpress.org/plugins/collapse-magic/) if you want an alternative.