
Hello anonymous user-7489 ,
By design, you aren't prompted for required information when you upload a file to a SharePoint Online library using the new experience version(modern mode).
As a workaround, I suggest you switch the Document library to classic mode or disable new experience feature at the site collection level. Then, upload document by clicking Upload button instead of drag-drop document.
Thanks,
Echo Du
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Updated Answer ==================
Hi anonymous user-7489 ,
Please following steps:
1.Switch the Document library to the Classic mode, click the Settings icon in the upper right corner, and then select Edit page
2.On the Editing page, click "Add a Web Part" link to add a ScriptEditor webpart
3.On the ScriptEditor webpart, click "EDIT SNIPPET" and apply the this code.
4.Click Stop Editing to exit edit.
Thanks,
Echo Du
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