Since Adobe does not continue to update flash11 later, it is only responsible for maintaining the security of the previously released version, so Firefox wants to watch the video completely without problems, and requires two steps:
1. Download and install the high version of Adobe Flash Player, it is worth noting that if the apt version in the Software center can not be found (you can first try to cancel the "software restricted by copyright or legal issues" check box), You can also download the tar.gz version, and then manually install (manual installation can refer to the second article reference content);
2. Install freshplayerplugin, execute command sudo add-apt-repository ppa:nilarimogard/webupd8 && sudo apt-get update && sudo apt-get install Freshplayerplugin, which contains three steps, first add a warehouse, then update, and then install
Firefox can't see video solutions in Ubuntu 16.04