.@TeamYouTube Can someone explain the error I'm getting when trying to upload a custom thumbnail?pic.twitter.com/ykUQf8GPOc
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We'd like to help. Have you tried clearing your browser’s cache & cookies: https://goo.gl/HZi6cx ? Also, try uploading it through Incognito mode or on a different browser to see if that makes a difference. Keep us posted.
I managed to get it to work outside of Chrome and on a different browser (Firefox to be exact). Also, going incognito in Chrome didn't work.
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