YouTube added a cool feature for those who watch long-form videos. If you’re logged in, you watched at least one minute from a video that’s longer than 20 minutes and there are more than 3 minutes left, then YouTube’s player has a neat surprise for you: close the page and when you open it again, the player resumes where you left off watching.
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Another change is that the HQ/HD flag is now sticky. Once you click on HQ or HD, YouTube will save the setting in a cookie and all the other videos will use the options, assuming that they have high-quality versions. “When you switch to view a video in high quality and lean back to enjoy the wide player experience, having to lean forward again to switch the experience back on, video after video, can be a real chore. Moving forward, your choice is sticky, meaning that when you go wide it will persist across your session.”