Hi Danny, is the problem that these sites are listed on the Firefox Home / new tab page in the initial shortcuts section? You can remove/block shortcuts, as described in the following article:

Customize items on your Firefox New Tab page

If the problem is that these sites appear in search results, there are add-ons that can hide unwanted search results. Here are two examples that I remember from years ago, but I don't know what is best today:

• https://addons.mozilla.org/firefox/addon/ublacklist/
• https://addons.mozilla.org/firefox/addon/hohser/

If there is some other problem, could you describe it in more detail?

You can look at these prefs in about:config to see what settings work for you to block media auto-play.

• media.autoplay.default = 5 [0:allow;1:blockAudible;5:blockAll]
• media.autoplay.blocking_policy = 2
• media.autoplay.allow-extension-background-pages => false
• media.autoplay.block-event.enabled => true
• media.block-autoplay-until-in-foreground

You can open about:config via the address/location bar. You can read the warning and click "Accept the Risk and Continue".

• https://support.mozilla.org/en-US/kb/about-config-editor-firefox

• https://support.mozilla.org/en-US/kb/block-autoplay