Am sure you problem probably is that you are unable to use IDM for downloading videos on google chrome and opera mini…, but other downloads work well with IDM. First make sure that you have version 6.23 build 3 (March 02/2015) or higher, otherwise IDM will not work well with browsers…
To download videos, you can use mozilla firefox as Internet download manager works great with mozilla firefox
If you love google chrome too much, then there is a browser you can download called torch browser. It basically runs on google chrome platform but has an additional feature that you can be able to download videos, its in built to the web browser…
that should help you…
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