IS THERE A CURE FOR KEEP FIREFOX AND STILL USING XP TO PLAY AND DOWNLOAD VIDS
Not really unless the alternate XP browsers work (I have yet to try any). Most sites play fine on Linux Mint + Firefox. If not, I use Windows 7 and the latest Firefox or Chrome.
I did notice Youtube recently fixed playback on XP with Firefox! That's right, after HTML5 video was broken for 2 years, they fixed it to work on XP. I'm shocked really, that they paid a programmer or 2 to get it working again for the millions of folks still using XP.
Stream capture on XP is largely broken. Only youtube-dl works on Youtube (they just put out a new version Oct 22, 2019 to fix audio).
Create some .bat files to make using youtube-dl easier. Some people use ffmpeg to Join the streams. I use mp4box but recently became concerned that it's recompressing the audio (need to test and research more). Someone has likely written a GUI wrapper for youtube-dl. Post if you know of one.
There are lots of other Youtube downloaders, but I haven't tried any yet. I use to use Flashgot until the developer jumped ship.
It doesn't matter that much now since Youtube cut the audio and video bitrate to 1/2 to 1/4th what it was in 2013 to 2015. I have videos recorded back then with 6Mbps video and 254Kbps audio. Google claims they never offered such high bitrates, but I have hundreds of videos that say otherwise. The higher bitrate makes a huge difference in quality.
I'm becoming capture illiterate on many sites now. Even my licensed copy of VideodownloadHelper on Win7 x64 with the latest Chrome and Firefox is having issues on many sites now. I have tried several screen recorder apps on my most powerful PC, but the quality blows compared to stream caps.
I think the folks creating the content protection systems are winning the battle- which will make this a very dark period in human history- if no one captures and shares the digital world, future historians will really be scratching their collective heads wondering why so much was lost.