Tested up to (plugin compatibility)
Every plugin states which versions it’s meant for. “Tested up to” names the newest WordPress version its author has tested it with. Next to it, “Requires at least” and “Requires PHP” name the oldest WordPress and PHP versions the plugin needs.
Why it matters
Section titled “Why it matters”“Tested up to” is a statement by the author, not a test of your site. A plugin tested up to an older WordPress release often works fine with a newer one, and a recent value doesn’t guarantee that it works with your theme and your other plugins. Right after a new WordPress release, many plugins are “not tested” for a few weeks, and that’s rarely a problem.
The minimum requirements are firmer: WordPress won’t activate a plugin that needs a newer WordPress or PHP version than the site has.
Still, a “Tested up to” that lags far behind is a hint. It can mean the author hasn’t looked at the plugin for a while; see unmaintained plugins.
What influences it
Section titled “What influences it”WordPress: The most common reason for a plugin that isn’t marked as tested with your WordPress version is a new WordPress release: authors need some time to test and update the value. Whether the plugin actually works also depends on the theme and the other plugins it runs with.
Server: The PHP version and the PHP extensions on the server have to meet the plugin’s requirements, independently of WordPress.
In Permo
Section titled “In Permo”The Not tested with … card is in System info, tab WordPress, under Plugins; its title names your WordPress version, such as “Not tested with 7.1”. It counts the active plugins whose “Tested up to” is older than that version and has no color, because this is information, not a problem. Permo compares only the first two numbers, the major release, so a plugin tested up to 7.1 counts as tested on 7.1.2. In the Active plugins list, such a plugin shows “Tested up to” with its older version.
The value comes from WordPress.org, so only plugins from the directory have it. A plugin that has an update waiting, or that is no longer maintained, counts there instead. Until Permo has the data from WordPress.org, the card doesn’t appear.