Today the media image editing function in my wordpress site suddenly had the problem of not being able to save the edited image, checking the console, and finding that the admin-ajax.php page reported a 500 error. To be safe, wordpress will disable the debug function by default, but there is no specific error description, the subsequent debug can not be carried out at all.
To find the exact reason for the error, I logged into the server
Open wp-config.php in the wordpress root directory.
locate
define('WP_DEBUG', false).modify to
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
Enable debug mode in wordpress, the second sentence means that by enabling WP_DEBUG_LOG, users can save all errors in the debug.log file
The debug.log file is in the /wp-content/ folder
On the frontend media page, re-edit the image and save it
Then look at the contents of the debug.log file
Here you can see that it is the aliyun-oss plugin incompatibility with the new version of wordpress that is causing the problem
Uninstalled the plugin, problem solved
Finally, don't forget to turn off debug mode
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