I have installed a couple of video download add-ons but they both don’t work.
“Download Flash & Video”, the menu button works but says" no videos/flash files found".
“YouTube Video Download and Convert” no buttons displayed under video as per instruction.
I have the utyoob video playing or paused but same. Tried other sites with flash/video but still same.
Firefox has been restarted since installing.
any ideers ?
FF quantum win7p x64
Have you contacted the developers about this? There’s usually support information in the add-on product page.
No, I had trouble finding contact info,
I just tried it now & is working, (both add-ons).
Thanks for poking me to test it again.
cheers
Stale topic, I know, but perhaps for future reference: video sites APIs can (and do change); YouTube in particular tries to do it often, I guess in an effort to throw off some awesome software frontends… Such as these two, for Android:
… Both are installable from F-Droid. 
P.S.
There used to be a amazingly-fantastic program for Windows, JDownloader (2.0) which we’ve lost along the way. The last update had been on May 26, 2016 and -now- strange things can happen when trying to install it; I’m unable to, even, test the offline installer as MEGA is using some outdated SSL certs, or something. 
EDIT: For anybody interested, just a -random- Reddit thread, “NewPipe vs SkyTube”.
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