The same thing happens to me both on Danbooru and in Twitter (for all Twitter gifs, but not for videos). Do you get this too?
assuming you guys are on windows 7. Disable Hardware acceleration in both Firefox and Chrome if you are using those web browsers. Works for most people. it happens you try to play MP4 files.
If you're on windows 8/10. Then your web browsers should be working fine.
I did my own little research since this was also affecting me. Long story short, its technically a windows 7 issue with more modern media shown on websites. and certain video formats.
assuming you guys are on windows 7. Disable Hardware acceleration in both Firefox and Chrome if you are using those web browsers. Works for most people. it happens you try to play MP4 files.
If you're on windows 8/10. Then your web browsers should be working fine.
I did my own little research since this was also affecting me. Long story short, its technically a windows 7 issue with more modern media shown on websites. and certain video formats.
The problem occurred for me when I was trying to view it on a machine running Max OS 10.10.5. I can view the file just fine on a machine running Windows 10.