Safari opens the Adobe Flash Player page on the Adobe website. Follow the instructions on the Adobe website to download and install the latest version of the plug-in. If you need to use an older version of Flash Player, you can use Internet plug-in management in Safari to run the plug-in in unsafe mode for websites that you trust. Nov 22, 2014 Question: Q: adobe flash not working os x yosemite 10.10.1 More Less Apple Footer This site contains user submitted content, comments and opinions and is.
Adobe Flash Player 16.0.0.305 is working for me with OS X Yosemite 10.10.2 on Safari Version 8.0.3.
From Apple:
Safari Power Saver.
Watch not. Waste not.
Many websites display animations using power-hungry plug-ins that can drain precious battery life. But OS X is watching out for you. The Safari Power Saver feature recognizes the difference between what you came to see and the stuff you probably didn’t. If the content is front and center, it plays as usual. But if it’s off in the margins, Safari Power Saver pauses it. You’ll see a static preview, and it won’t run until you click to play it. So if you don’t want to watch something, it won’t take a toll on your battery life.
1. Check to see if Flash is installed and working: https://helpx.adobe.com/flash-player.html
2. Check Safari Preferences:

Safari > Preferences > Advanced
Adobe Flash Player For Mac Os X
Safari > Preferences > Security
Safari > Preferences > Security > Website Settings
Feb 7, 2015 11:08 AM
Adobe Flash Player for Mac lets you access Flash content in Web sites when using browsers like OS X's Safari. The plug-in integrates seamlessly and through a preference pane, gives you control over the type of access each Web site has to your system. The only downside to using it is that it suffers from performance issues.
Pros
Configurable: The plug-in adds a new preference pane in System Preferences where you will be able to adjust your local storage, camera, mic and peer-assisted networking settings to either allow the feature for all Web sites, on a per-request basis, or to deny all requests.
Per-site settings: All the features listed above support per-site settings for even more precise control.
Advanced options: The app lets you delete all Flash-related data and settings as well as audio and video license files, deauthorize the computer, and access trusted locations for developer testing.
Cons
Performance issues: Despite its long history with OS X, this software tends to slow down your computer and drain your battery.
Download Adobe Flash Player For Mac
Bottom Line
Download Adobe Flash Player For Mac
If you're constantly visiting Flash-based Web sites, you will have to install either this plug-in, or a browser like Google Chrome, which has built-in Flash support. Generally, the better way to go would be to use Chrome since there will be a lower performance impact on your system. But if Chrome is not your kind of browser, then this plug-in remains a viable solution for enjoying Flash content on your Mac.