Sometimes a plugin release contains an important breaking change. Maybe it requires a newer PHP version, maybe it removes an old API, or maybe it needs a migration step before users update. In those cases it helps a lot to show an obvious warning directly on the plugins list screen.
Older WordPress versions used to display the Upgrade Notice section from readme.txt automatically, but recent versions stopped surfacing it in the plugin list. We can add that reminder back ourselves.
An example of an upgrade notice in readme.txt
The section heading must stay as ## Upgrade Notice ##. Under it, each version gets its own heading such as ### 1.8 ###, followed by the warning message shown to users.
## Upgrade Notice ##
### 1.8 ###
This release deprecates the old class-based way of building multi-condition queries. Check your theme before updating.
### 1.7 ###
This version requires PHP 5.4 or newer. Do not update if your server is running an older PHP version.Add the notice back to the plugins list
WordPress fires the dynamic action hook in_plugin_update_message-{$plugin_file} when it renders the update row for a specific plugin. Hook into it, compare the installed version with the new version, and then print the warning text from the release metadata.
add_action(
'in_plugin_update_message-wizhi-multi-filters/wizhi-multi-filter.php',
'showUpgradeNotification',
10,
2
);
function showUpgradeNotification($currentPluginMetadata, $newPluginMetadata) {
if (empty($newPluginMetadata->upgrade_notice)) {
return;
}
echo '<br /><span style="color:#d54e21;">';
echo wp_kses_post($newPluginMetadata->upgrade_notice);
echo '</span>';
}If you want to be stricter, you can also check version numbers and only show the warning for major releases. That keeps the plugin screen cleaner when the update is just a routine maintenance release.
Summary
This is a small enhancement, but it makes plugin maintenance much safer. Users are far more likely to notice a warning on the actual update row than they are to open a readme file before clicking the update button.
