Restrict File Type(.exe,.dll files) upload to document library in ModernSharepoint?

Question

Answer 1

Hi @Srikanth Manga ,
There is no OOTB facility with SharePoint Online to restrict specific file extensions in SharePoint Online.
But after my research and testing , I can create a flow as a workaround that will auto-runs on each file upload and if it doesn't match the given type or extension (.exe ,.dll in your case), auto-delete that document and send email to the author who uploaded it.
Compose 2 inputs：

last(split(triggerOutputs()?['body/{FilenameWithExtension}'],'.'))  

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