Latest version on mac frozen at accept/deny window

The easiest workaround is just to go to Control Panel > Flash Player > Storage and choose Allow sites to save information on this computer.

The anti-clickjacking logic is preventing clicks on the dialog in this scenario. We should not be able to accept clicks on dialogs that are obscured, but it's really, really difficult from the perspective of a plug-in in the browser to know whether or not we're actually on top once everything is composited by the browser and rendered to screen.  If there's stuff moving behind the dialog in the background, that's definitely problematic, but there are plenty of other (often resolution-specific) times where we see false-positives.  While it's little consolation, it's failing in a "too-secure" way, which is better than the opposite...

What we'd like to ultimately do is get rid of all of those dialogs and move them into the browser, where you know that the dialog is visible and the clicks are authoritative, but that requires buy-in from the browser vendors and new APIs for us to use, which is by no means a guarantee.

What we did learn in the initial conversations, particularly around the storage dialog, is that any complexity beyond Allow/Deny makes that a non-starter.  We've changed the behavior to something closer to an all-or-nothing approach as a first step down that road.  In the early 90's when that functionality was introduced, 100k of disk space might have mattered to someone, but in 2016, the available increments were kind of comical in comparison to commodity hard disk sizes.

It's also the case that HTML5 facilities have largely supplanted Flash Player's Local Shared Objects as the method of choice for resilient tracking tokens, so setting Local Storage Settings to anything but Allow isn't really buying you anything in terms of increased privacy.  I've written about that a lot, and cited academic sources -- if you're interested, you can find those posts in my activity history.

Clearing your browser cookies also clears the Flash Player LSO stores automatically.  All the initial paranoia about Flash Cookies in the late 90's early 2000's has been largely solved for many years, and in fact, we go beyond that to obscure data points that might otherwise be used to fingerprint you (like font enumeration) when you're in your browser's private/incognito mode.

The best solution if you're looking for privacy at this point is to just leave things default and use your browser's private browsing mode as appropriate, and if you want to avoid marketers' server-side tracking, use a commercial proxy service in addition to private browsing mode.

Finally, moving to an older version of Flash Player will also expose you to all of the security issues that have been patched in previous releases.   Motivated, well-funded attackers actively reverse-engineer our fixes to determine what can be attacked in older versions, making moving to a vulnerable version a risky course of action in general.  In an age where we're making continuous security improvements based on the latest research and collaborations from some of the best engineers and organizations involved in software security, all old versions are theoretically vulnerable.

If you absolutely must do it, you can find old versions on our archives page, but I'd strongly recommend limiting your use of old Flash versions to just the applications you need it for, and use a dedicated browser with a current Flash Player for everything else.