How to stop the install Adobe Flash popup without having to install the plugin; in IE it can be done by turning the "ActiveX Filtering" on. When it's on, you won't get the following popup:
This website wants to install the following add-on 'Adobe Flashruntime' from 'Adobe Systems Incorporated'.
I'm not sure which version of Internet Explorer introduced "ActiveX Filtering". v10 has it in the Tools menu.
When Active X Filtering is on it seems that IE is literally stripping out any ActiveX calls from the web page. I'm assuming that’s what it does and why it stops the annoying popup.
For any web page that you want an ActiveX control to be available, turn the "ActiveX Filtering" off. I rarely run into any web pages where anything that needs ActiveX is of any importance so having ActiveX blocked is just fine.
You will see an icon indicator come on in the browser if the web page has ActiveX calling code. So, if something in the web page isn't working that you actually care about, then look for the ActiveX indicator. If the indicator is visible then you can try turning ActiveX Filtering off to see if an ActiveX control call is needed for the web page. If so, then you simply remember to have the filter off when you use that web site. For me, I only have one web site that I need to turn the filter off for because I actually need what the ActiveX control provides.
I hate how the Adobe Flash media sucks the life out of CPU resources when browsing the internet so I too refuse to install the plugin. Seriously, it's this kind of garbage that causes computer lay people to throw away perfectly good computers for quad cores.
PS when I absolutely need to see Flash media then I use Chrome since it has a built in Flash media plugin.