Extensions for Tor Browser

I am using browser extensions, especially a adblocker for the tor browser.
Do these extensions also use the tor network, or can they connect via the normal connection of my computer?
Apart from that, do adblockers need an own internet connection, for example for retrieving data from filter lists?
I also use scripts to hide my adblocker from websites, if this is important.
All I need to know, is if the usage of adblockers can uncover my internet activities to anyone.

your question is a little complicated. Generally its not a good idea to install your own add ons to Tor Browser.

Reason being because some add ons you think keep your privacy may not actually do so.

Example. Many people used to use or still use an add on called “ghostery”. I will call them out because while they hide ads they have in the past not cared for user privacy by collecting metrics for users for their own uses.

And yes generally ad blockers do need an internet connection. Now the way tor Browser is configured when add ons need to access the internet the add on’s access to the internet is also proxied through Tor.

It doesn’t matter if you use ghostery, ad block plus, or ublock origin all of the popular ad blockers will get a list of domains they need to block from a list on somewhere on the internet (but like some popular block lists like fanboy is hosted on github)

If memory serves the reason why Tor Browser does not include an ad blocker is because

  1. these ad block lists can be hijacked via DNS
  2. they can be used by ISPs and local network admins to co-relate what path you are taking through Tor. (granted the ISP and network admin have to know that you are using Tor and an Ad blocker)