Sometimes the problem with Flash is that the installer didn't clear out the old DLL so Firefox reports the older version number to sites. You could check my plugin lister page to see whether it detects multiple Shockwave Flash versions:

https://jeffersonscher.com/res/plugins.html

Meanwhile, Google and Microsoft partnered with Adobe to integrate Flash directly into Chrome and Edge, so Mozilla isn't going to be able to move this mountain on its own. (Not that it isn't trying: http://www.areweflashyet.com/shumway/)

You probably know about this, but just in case...

You can limit Flash ads by setting Flash to Click-to-Play ("Ask to Activate"). This will delay Flash from starting on a page until you approve it.

To set "Ask to Activate", open the Add-ons page using either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Plugins. Look for "Shockwave Flash" and change "Always Activate" to "Ask to Activate".

With this setting, when you visit a site that wants to use Flash, you should see a notification icon in the address bar and usually (but not always) one of the following: a link in a black rectangle in the page or an infobar sliding down between the toolbar area and the page.

The plugin notification icon in the address bar typically looks like a small, dark gray Lego block. (It turns red when it's considered vulnerable.)

If you see a good reason to use Flash, and the site looks trustworthy, you can go ahead and click the notification icon in the address bar to allow Flash. You can trust the site for the time being or permanently.

But if the page only wants to use Flash for ads, tracking, or irritating background music, feel free to ignore the notification! It will just sit there in case you want to use it later.

If you want finer control: This extension addresses the issue of only wanting some videos on a page to play: https://addons.mozilla.org/firefox/addon/click-to-play-per-element/ (I haven't tried it myself)

Thank y'all for your prompt replies and sincerity. However...

For what it is worth, if we have to have flashy and intrusive ads, then I prefer the HTML5 approach. Of course, I'm speaking from the position of less annoying and less intrusive being better, whereas Adobe is clearly driven by the advertisers who are in an arms race to annoy us to death.

Yes, I know that Mozilla can't force that transition away from Flash, but much of the so-called "value" that drives Adobe's continuing propagation of Flash and the advertisers' preference for Flash ads is their support by browsers, including Mozilla. In some ways I don't like Apple and in most ways I don't like Steve Jobs, but disliking Adobe is increasingly likeable to me... If Mozilla starts pushing against Flash, that in itself will reduce the value and help it disappear sooner rather than later.

And yes, I am quite aware of that setting for controlling Adobe and tend to use it on any of my machines that need higher levels of security. However, in general I want LESS complexity, and Adobe's approach FAILS on that that criterion, too. Hard to know what information to include on such comments, but I'm pretty experienced with computers and so forth... However, I feel like my solution approach to this problem is more economic or even political, not technical. If I haven't made it clear, I think that Adobe Flash is FAR beyond any hope of technical redemption.