Web browsers and streaming sites change their protocols constantly. Patched versions cannot be updated through the official Internet Download Manager Updates channel without breaking the activation. This means your download extension will quickly stop working on modern websites.
Operating a licensed, up-to-date version directly from the developer yields the best utility.
Official downloads include the correct signed extensions for your browsers via the Internet Download Manager Extension Setup page.
Official IDM splits files into multiple streams dynamically to maximize your bandwidth limits safely.