Question - warning messages about missing plugins

Well, I am using Xerobank browser right now (along with NoScript) and every time I open pages of some kind this pop-up is being showed:

Additional plugins are required to display all the media on this page. (Install Missing Plugins...)

And also:

Click here to download plugin. (from Youtube videos placed on the page source, for example). This message is being showed instead of the image or video.

All I want to do is to block these warnings from my browser. Is that possible?

Correct me if I'm wrong: Flash is required to display all these videos or images. So, if I proceed and install this plugin, my privacy is no longer secure, and this is another way to find out my real IP. May I proceed and install these missing plugins? What do you think?

See my concerns here:

https://www.wilderssecurity.com/showthread.php?p=1027251

And sometimes while the page is being loaded all images are being replaced by a red point. Is this some kind of bug?