Regarding the remove of the Ext JS Library in 2024.1, is this only an issue if we have customizations that interact with info outside of NetSuite? We do have a small number (but extremely critical) scripts in NetSuite, but they all do stuff just within NS, so I assume we're ok. Where would I go to check this? We don't have SuiteScripting resources internally. Thanks!

You can use the ExtJS inside NetSuite to show pop-ups. So, it is an issue if your NetSuite scripts are using ExtJS.