All my plugins include a Debug Mode. This should be considered an advanced feature for advanced users.
For OMGF (Pro), it can be enabled from within Advanced Settings. When a log file has been generated, it'll be available for download.
For your own safety, OMGF (Pro) stops logging when the file reaches a size of 1MB after which an option will appear allowing you to delete the log file, accompanied by a clear warning.
Adding additional debug points in OMGF (Pro)
You can invoke the debugger anywhere in the plugin's code, by calling the following static method:
$message can be either a string or an array. When printing an array, make sure to wrap it in
print_r($message, true); e.g.
OMGF::debug(print_r([ 'test' => 'test'], true));
Or when printing a string:
OMGF::debug("testing testing, 1 2 3.');
All debug information is stored in a file called omgf-debug.log and is located in the wp-content folder. It is available for download under the Advanced Settings tab.