Depreciated jQuery reported by jQuery Migrate Plugin

## From jQuery Migrate Plugin

https://wordpress.org/plugins/enable-jquery-migrate-helper/

`jQuery.fn.unload() is deprecated | Plugin: o2 | https://****/wp-content/plugins/o2/modules/offline/js/offline.js`

` \'ready\' event is deprecated | Plugin: o2 | https://****/wp-content/plugins/o2/js/editor/editor.js`

### False Positives

`wp-content/plugins/o2/modules/notifications/js/app/notifications.js` leverages the event `ready.o2`, which jQuery Migrate Plugin picks up as a false positive.

### Solution: ready event is depreciated

I'm following this article as a guide: https://api.jquery.com/ready/

`wp-content/plugins/o2/js/editor/editor.js:84`

replace

`
$doc.on( 'ready', function() {
`

with

`
$(function() {
`

### Solution: unload is depreciated

I'm following this guide:
https://stackoverflow.com/questions/46443032/what-is-a-foolproof-alternative-to-window-unload/46443788

`/wp-content/plugins/o2/modules/offline/js/offline.js:31`

Change

`
jQuery( window ).unload( function() {
o2.Offline.onWindowUnloading();
} );
`
To

`
jQuery( window ).on( 'beforeunload' , function() {
o2.Offline.onWindowUnloading();
} );
`

Inspect wp-content/plugins/o2/js/editor/editor.js:84 and wp-content/plugins/o2/modules/offline/js/offline.js:31, then review notifications.js to distinguish the reported false positive. Verify the two deprecated jQuery usages are addressed and that the jQuery Migrate warnings no longer appear for these files.

Written by the indexing model from the issue text.