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Microsoft ending support for Windows 10 could send 240 million PCs to landfills: Report - CNA
(www.channelnewsasia.com)
This is a most excellent place for technology news and articles.
Software updates will stop and render the possibility of an unsafe system more and more over time. Since there are no updates, if a backdoor is found it won't be patched.
Besides that you'll probably be able to use it for a few more years as long as your apps still work