A few weeks ago, some streaming videos stopped working. On some websites they work and on others they don't. When they don't work, I'll see a white square where the video should be playing. There's a tiny box in the upper-left-hand corner of the white sqare with a little blue triangle, green circle and red square in it.
Why would it all of the sudden start doing this? Why is it only on some web pages? How do I fix it?
Any help would be greatly appriciated. Thanks.

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