In the list of apps you listed most are trying to "get around" YouTube policy so you should see them crash and fail. This is not a sign there is something wrong with your PC.
If you feel the apps/addons/etc should not fail, you have to take this up with the app authors.
I have a problem that only seems to affect certain programs: my web browsers, the Youtube Downloader part of Ninja Download Manager, and MEGAsync. The affected programs crash. A lot. Since it's only one process, when this happens in Waterfox, the entire program crashes, making it unusual.
For the Youtube Downloader part of Ninja Download Manager, this just makes it not recognize Youtube videos unless I get lucky or try again a bunch of times. For MEGAsync, on occasion it will reach the end of a download, scrap it, and try downloading it again.
And for Chrome, my extensions crash constantly and I get a LOT of "Aw, Snap!" and "Can't open this page" errors, as well as pages that only half load, all which are often only solved with a great deal of hard refreshes or cache emptying. Also, a lot of the time, both images and videos get graphical glitches, and images also sometimes don't finish loading and, again, must be given a hard refresh. In addition, specific websites get additional errors. Mega often gives out errors, the Youtube player crashes, often when hitting an unloaded section of the video, and the Discord website often just gives me a blank page. Note that it's only Youtube that this happens with; other video websites play fine, other than the aformentioned graphical errors and the entire page crashing.
This doesn't seem to be a network issue, since Vuze and Ninja Download Manager (once it's started a download) can still download files fine. Also, this problem has occasionally stopped at random after copious restarting, only to come back the next time the computer is turned off.
My operating system is Windows 7, by the way.
I would appreciate any help that could be provided, this is getting really annoying.

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