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The above video-link seems to be deleted from youtube for some reason, that did produce the most problems but however the browser does still redirect by some links instead of directly downloading, like if I try below:

It redirects to below link:

https://r4---sn-5hnedn7e.googlevideo.com/videoplayback?ratebypass=yes&sparams=clen,dur,ei,expire,gir,id,ip,ipbits,ipbypass,itag,lmt,mime,mip,mm,mn,ms,mv,pl,ratebypass,requiressl,source&ipbits=0&requiressl=yes&txp=5431432&dur=229.389&id=o-APJeJek7F_b5CR8JkJX8AyxgHJ7Fp6qiREtQz0mUOEx3&lmt=1540529660670586&key=cms1&ip=118...

and kind of a video-player with download option is visible which could be related to the browser "Vivaldi" but this time at least there is no redirect to *.exe involved