Ever since upgrading to Sierra, I've noticed a strange problem. Embedded flash video on Facebook and Youtube flickers rapidly. I've noticed it in Google Chrome and Safari. I've upgraded to the latest Chrome and latest flash player for both browsers. It happens when viewing animated GIF's as well encoded as GIFV.
FWIW, YouTube has been using HTML5 for quite awhile so flash should have nothing to do with it. Chrome has flash built in so there is no need to download flash for Chrome.
I don't go on Facebook so I can't comment on that. I also don't know where I can test a GIFV nor do I know why it would need flash.
It's a strange thing. Sometimes a video will play fine, then another on the same page won't. I'm running a 2015 MacBook Pro as well. You can find GIFV's on Imgur. Here is a detail on the format. https://help.imgur.com/hc/en-us/articles/208606616-What-is-GIFV-
I just viewed a video on facebook that did this same thing. Went to the video URL specifically in a new Chrome tab and it didn't have a problem. I wonder if it's got something to do with buffering.
Thanks for the link. I can watch the GIFV videos without any issue on igmur in Firefox, Safari and Chrome. GIFV videos use an MP4 container apparently so flash shouldn't be involved either.
The issue you're having could just be temporary.
It could be buffering, Facebook could be busy.
Flash video and Gifv flickering on websites
