Adobe released an update today to resolve the critical issues it admitted were in the 18.0.0.203 version. You can get 18.0.0.209 on this page:

https://www.adobe.com/products/flashplayer/distribution3.html

In the first table, look for the row for "plugin-based browsers" and you can use either the EXE or the MSI installer.

No one can promise that this kind of block will never happen again. Should that occur, if you are not accustomed to using the "Ask to Activate" feature for a plugin, here's what to expect:

When you visit a site that wants to use Flash, you should see a notification icon in the address bar and 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.

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

But some pages use Flash only for tracking or playing ads, so if you don't see an immediate need for Flash, feel free to ignore the notification! It will just sit there in case you want it later.

Hi

The block you mention was for a particular version of Flash that has now been updated. You should be able to install version 18.0.0.209 from Adobe following the steps in this article.

Firefox does not need this to play all videos online. You can see videos that are available in HTML5 (such as popular video sharing site Youtube) without any additional software.

I hope this helps, but if you have any further queries, please come back here and we will do our best to help.

Thanks to both of you! Got your emails back-to-back and both had essentially the same solution.