If you have worked with Script Editor webpart in IE you would have noticed that you do not get the flexibility to increase the height of it. You can use other browsers and get around this limitation. To work around this in IE isn't very difficult, use the following style and you can set the height of the webpart easily: <style> .ms-rte-embeddialog-textarea{ height:600px; </style> By manipulating the class ms-rte-embeddialog-textarea we can vary the height of the Script Editor webpart. The above style has to be within the webpart.
Practical notes on Microsoft 365, SharePoint Online, Entra, Azure and PowerShell - from an IT consultant who's been working with Microsoft technologies since 2004.